A CML dictionary of the IUCR standard CIF CORE DEFINITIONS available from the IUCR website
(http://www.iucr.org/resources/cif/dictionaries/cif_core).
Corresponds to the _atom_site_adp_type term in the IUCr Core CIF dictionary.
A standard code used to describe the type of atomic displacement parameters used for the site.
atom_site
Uani
Uiso
Uovl
Umpe
Bani
Biso
Bovl
These are the standard anisotropic atomic displacement components in angstroms squared which appear
in the structurefactor term T = exp{(1/4) sum~i~ [ sum~j~ (B^ij^ h~i~ h~j~ a*~i~ a*~j~) ] } h = the
Miller indices a* = the reciprocalspace cell lengths The unique elements of the real symmetric matrix
are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting
atomic displacement parameters. U, being directly proportional to B, is preferred.
atom_site
Corresponds to the _atom_site_aniso_b_11 term in the IUCr Core CIF dictionary.
These are the standard anisotropic atomic displacement components in angstroms squared which appear
in the structurefactor term T = exp{(1/4) sum~i~ [ sum~j~ (B^ij^ h~i~ h~j~ a*~i~ a*~j~) ] } h = the
Miller indices a* = the reciprocalspace cell lengths The unique elements of the real symmetric matrix
are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting
atomic displacement parameters. U, being directly proportional to B, is preferred.
atom_site
Corresponds to the _atom_site_aniso_b_12 term in the IUCr Core CIF dictionary.
These are the standard anisotropic atomic displacement components in angstroms squared which appear
in the structurefactor term T = exp{(1/4) sum~i~ [ sum~j~ (B^ij^ h~i~ h~j~ a*~i~ a*~j~) ] } h = the
Miller indices a* = the reciprocalspace cell lengths The unique elements of the real symmetric matrix
are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting
atomic displacement parameters. U, being directly proportional to B, is preferred.
atom_site
Corresponds to the _atom_site_aniso_b_13 term in the IUCr Core CIF dictionary.
These are the standard anisotropic atomic displacement components in angstroms squared which appear
in the structurefactor term T = exp{(1/4) sum~i~ [ sum~j~ (B^ij^ h~i~ h~j~ a*~i~ a*~j~) ] } h = the
Miller indices a* = the reciprocalspace cell lengths The unique elements of the real symmetric matrix
are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting
atomic displacement parameters. U, being directly proportional to B, is preferred.
atom_site
Corresponds to the _atom_site_aniso_b_22 term in the IUCr Core CIF dictionary.
These are the standard anisotropic atomic displacement components in angstroms squared which appear
in the structurefactor term T = exp{(1/4) sum~i~ [ sum~j~ (B^ij^ h~i~ h~j~ a*~i~ a*~j~) ] } h = the
Miller indices a* = the reciprocalspace cell lengths The unique elements of the real symmetric matrix
are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting
atomic displacement parameters. U, being directly proportional to B, is preferred.
atom_site
Corresponds to the _atom_site_aniso_b_23 term in the IUCr Core CIF dictionary.
These are the standard anisotropic atomic displacement components in angstroms squared which appear
in the structurefactor term T = exp{(1/4) sum~i~ [ sum~j~ (B^ij^ h~i~ h~j~ a*~i~ a*~j~) ] } h = the
Miller indices a* = the reciprocalspace cell lengths The unique elements of the real symmetric matrix
are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting
atomic displacement parameters. U, being directly proportional to B, is preferred.
atom_site
Corresponds to the _atom_site_aniso_b_33 term in the IUCr Core CIF dictionary.
Corresponds to the _atom_site_aniso_label term in the IUCr Core CIF dictionary.
Anisotropic atomic displacement parameters are usually looped in a separate list. If this is the
case, this code must match the _atom_site_label of the associated atom in the atom coordinate list and
conform with the same rules described in _atom_site_label.
atom_site
Corresponds to the _atom_site_aniso_ratio term in the IUCr Core CIF dictionary.
Ratio of the maximum to minimum principal axes of displacement (thermal) ellipsoids.
atom_site
Corresponds to the _atom_site_aniso_type_symbol term in the IUCr Core CIF dictionary.
This _atom_type_symbol code links the anisotropic atom parameters to the atomtype data associated
with this site and must match one of the _atom_type_symbol codes in this list.
atom_site
These are the standard anisotropic atomic displacement components in angstroms squared which appear
in the structurefactor term T = exp{2pi^2^ sum~i~ [sum~j~ (U^ij^ h~i~ h~j~ a*~i~ a*~j~) ] } h = the
Miller indices a* = the reciprocalspace cell lengths The unique elements of the real symmetric matrix
are entered by row.
atom_site
Corresponds to the _atom_site_aniso_u_11 term in the IUCr Core CIF dictionary.
These are the standard anisotropic atomic displacement components in angstroms squared which appear
in the structurefactor term T = exp{2pi^2^ sum~i~ [sum~j~ (U^ij^ h~i~ h~j~ a*~i~ a*~j~) ] } h = the
Miller indices a* = the reciprocalspace cell lengths The unique elements of the real symmetric matrix
are entered by row.
atom_site
Corresponds to the _atom_site_aniso_u_12 term in the IUCr Core CIF dictionary.
These are the standard anisotropic atomic displacement components in angstroms squared which appear
in the structurefactor term T = exp{2pi^2^ sum~i~ [sum~j~ (U^ij^ h~i~ h~j~ a*~i~ a*~j~) ] } h = the
Miller indices a* = the reciprocalspace cell lengths The unique elements of the real symmetric matrix
are entered by row.
atom_site
Corresponds to the _atom_site_aniso_u_13 term in the IUCr Core CIF dictionary.
These are the standard anisotropic atomic displacement components in angstroms squared which appear
in the structurefactor term T = exp{2pi^2^ sum~i~ [sum~j~ (U^ij^ h~i~ h~j~ a*~i~ a*~j~) ] } h = the
Miller indices a* = the reciprocalspace cell lengths The unique elements of the real symmetric matrix
are entered by row.
atom_site
Corresponds to the _atom_site_aniso_u_22 term in the IUCr Core CIF dictionary.
These are the standard anisotropic atomic displacement components in angstroms squared which appear
in the structurefactor term T = exp{2pi^2^ sum~i~ [sum~j~ (U^ij^ h~i~ h~j~ a*~i~ a*~j~) ] } h = the
Miller indices a* = the reciprocalspace cell lengths The unique elements of the real symmetric matrix
are entered by row.
atom_site
Corresponds to the _atom_site_aniso_u_23 term in the IUCr Core CIF dictionary.
These are the standard anisotropic atomic displacement components in angstroms squared which appear
in the structurefactor term T = exp{2pi^2^ sum~i~ [sum~j~ (U^ij^ h~i~ h~j~ a*~i~ a*~j~) ] } h = the
Miller indices a* = the reciprocalspace cell lengths The unique elements of the real symmetric matrix
are entered by row.
atom_site
Corresponds to the _atom_site_aniso_u_33 term in the IUCr Core CIF dictionary.
Corresponds to the _atom_site_attached_hydrogens term in the IUCr Core CIF dictionary.
The number of hydrogen atoms attached to the atom at this site excluding any hydrogen atoms for
which coordinates (measured or calculated) are given.
atom_site
Corresponds to the _atom_site_b_equiv_geom_mean term in the IUCr Core CIF dictionary.
Equivalent isotropic atomic displacement parameter, B(equiv), in angstroms squared, calculated as
the geometric mean of the anisotropic atomic displacement parameters. B(equiv) = (B~i~ B~j~ B~k~)^1/3^
B~n~ = the principal components of the orthogonalized B^ij^ The IUCr Commission on Nomenclature
recommends against the use of B for reporting atomic displacement parameters. U, being directly
proportional to B, is preferred.
atom_site
Corresponds to the _atom_site_b_iso_or_equiv term in the IUCr Core CIF dictionary.
Isotropic atomic displacement parameter, or equivalent isotropic atomic displacement parameter,
B(equiv), in angstroms squared, calculated from anisotropic displacement components. B(equiv) = (1/3)
sum~i~[sum~j~(B^ij^ a*~i~ a*~j~ a~i~ a~j~)] a = the realspace cell lengths a* = the reciprocalspace
cell lengths B^ij^ = 8 pi^2^ U^ij^ Ref: Fischer, R. X. & Tillmanns, E. (1988). Acta Cryst. C44,
775776. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic
displacement parameters. U, being directly proportional to B, is preferred.
atom_site
Corresponds to the _atom_site_calc_attached_atom term in the IUCr Core CIF dictionary.
The _atom_site_label of the atom site to which the 'geometry calculated' atom site is attached.
atom_site
Corresponds to the _atom_site_calc_flag term in the IUCr Core CIF dictionary.
A standard code to signal whether the site coordinates have been determined from the intensities or
calculated from the geometry of surrounding sites, or have been assigned dummy coordinates. The
abbreviation 'c' may be used in place of 'calc'.
atom_site
d
calc
c
dum
The atomsite coordinates in angstroms specified according to a set of orthogonal Cartesian axes
related to the cell axes as specified by the _atom_sites_Cartn_transform_axes description.
atom_site
Corresponds to the _atom_site_cartn_x term in the IUCr Core CIF dictionary.
The atomsite coordinates in angstroms specified according to a set of orthogonal Cartesian axes
related to the cell axes as specified by the _atom_sites_Cartn_transform_axes description.
atom_site
Corresponds to the _atom_site_cartn_y term in the IUCr Core CIF dictionary.
The atomsite coordinates in angstroms specified according to a set of orthogonal Cartesian axes
related to the cell axes as specified by the _atom_sites_Cartn_transform_axes description.
atom_site
Corresponds to the _atom_site_cartn_z term in the IUCr Core CIF dictionary.
Corresponds to the _atom_site_chemical_conn_number term in the IUCr Core CIF dictionary.
This number links an atom site to the chemical connectivity list. It must match a number specified
by _chemical_conn_atom_number.
atom_site
Corresponds to the _atom_site_constraints term in the IUCr Core CIF dictionary.
A description of the constraints applied to parameters at this site during refinement. See also
_atom_site_refinement_flags and _refine_ls_number_constraints.
atom_site
Corresponds to the _atom_site_description term in the IUCr Core CIF dictionary.
A description of special aspects of this site. See also _atom_site_refinement_flags.
atom_site
Corresponds to the _atom_site_disorder_assembly term in the IUCr Core CIF dictionary.
A code which identifies a cluster of atoms that show longrange positional disorder but are locally
ordered. Within each such cluster of atoms, _atom_site_disorder_group is used to identify the sites that
are simultaneously occupied. This field is only needed if there is more than one cluster of disordered
atoms showing independent local order.
atom_site
Corresponds to the _atom_site_disorder_group term in the IUCr Core CIF dictionary.
A code which identifies a group of positionally disordered atom sites that are locally
simultaneously occupied. Atoms that are positionally disordered over two or more sites (e.g. the
hydrogen atoms of a methyl group that exists in two orientations) can be assigned to two or more groups.
Sites belonging to the same group are simultaneously occupied, but those belonging to different groups
are not. A minus prefix (e.g. "1") is used to indicate sites disordered about a special position.
atom_site
Atomsite coordinates as fractions of the _cell_length_ values.
atom_site
Corresponds to the _atom_site_fract_x term in the IUCr Core CIF dictionary.
Atomsite coordinates as fractions of the _cell_length_ values.
atom_site
Corresponds to the _atom_site_fract_y term in the IUCr Core CIF dictionary.
Atomsite coordinates as fractions of the _cell_length_ values.
atom_site
Corresponds to the _atom_site_fract_z term in the IUCr Core CIF dictionary.
Corresponds to the _atom_site_label term in the IUCr Core CIF dictionary.
The _atom_site_label is a unique identifier for a particular site in the crystal. This code is made
up of a sequence of up to seven components, _atom_site_label_component_0 to *_6, which may be specified
as separate data items. Component 0 usually matches one of the specified _atom_type_symbol codes. This
is not mandatory if an _atom_site_type_symbol item is included in the atomsite list. The
_atom_site_type_symbol always takes precedence over an _atom_site_label in the identification of the
atom type. The label components 1 to 6 are optional, and normally only components 0 and 1 are used. Note
that components 0 and 1 are concatenated, while all other components, if specified, are separated by an
underscore. Underscores are only used if higherorder components exist. If an intermediate component is
not used, it may be omitted provided the underscore separators are inserted. For example, the label
'C233__ggg' is acceptable and represents the components C, 233, '' and ggg. Different labels may have a
different number of components.
atom_site
Component 0 is normally a code which matches identically with one of the _atom_type_symbol codes.
If this is the case, then the rules governing the _atom_type_symbol code apply. If, however, the data
item _atom_site_type_symbol is also specified in the atomsite list, component 0 need not match this
symbol or adhere to any of the _atom_type_symbol rules. Component 1 is referred to as the "atom number".
When component 0 is the atomtype code, it is used to number the sites with the same atom type. This
component code must start with at least one digit which is not followed by a + or  sign (to distinguish
it from the component 0 rules). Components 2 to 6 contain the identifier, residue, sequence, asymmetry
identifier and alternate codes, respectively. These codes may be composed of any characters except an
underscore.
atom_site
Corresponds to the _atom_site_label_component_0 term in the IUCr Core CIF dictionary.
Component 0 is normally a code which matches identically with one of the _atom_type_symbol codes.
If this is the case, then the rules governing the _atom_type_symbol code apply. If, however, the data
item _atom_site_type_symbol is also specified in the atomsite list, component 0 need not match this
symbol or adhere to any of the _atom_type_symbol rules. Component 1 is referred to as the "atom number".
When component 0 is the atomtype code, it is used to number the sites with the same atom type. This
component code must start with at least one digit which is not followed by a + or  sign (to distinguish
it from the component 0 rules). Components 2 to 6 contain the identifier, residue, sequence, asymmetry
identifier and alternate codes, respectively. These codes may be composed of any characters except an
underscore.
atom_site
Corresponds to the _atom_site_label_component_1 term in the IUCr Core CIF dictionary.
Component 0 is normally a code which matches identically with one of the _atom_type_symbol codes.
If this is the case, then the rules governing the _atom_type_symbol code apply. If, however, the data
item _atom_site_type_symbol is also specified in the atomsite list, component 0 need not match this
symbol or adhere to any of the _atom_type_symbol rules. Component 1 is referred to as the "atom number".
When component 0 is the atomtype code, it is used to number the sites with the same atom type. This
component code must start with at least one digit which is not followed by a + or  sign (to distinguish
it from the component 0 rules). Components 2 to 6 contain the identifier, residue, sequence, asymmetry
identifier and alternate codes, respectively. These codes may be composed of any characters except an
underscore.
atom_site
Corresponds to the _atom_site_label_component_2 term in the IUCr Core CIF dictionary.
Component 0 is normally a code which matches identically with one of the _atom_type_symbol codes.
If this is the case, then the rules governing the _atom_type_symbol code apply. If, however, the data
item _atom_site_type_symbol is also specified in the atomsite list, component 0 need not match this
symbol or adhere to any of the _atom_type_symbol rules. Component 1 is referred to as the "atom number".
When component 0 is the atomtype code, it is used to number the sites with the same atom type. This
component code must start with at least one digit which is not followed by a + or  sign (to distinguish
it from the component 0 rules). Components 2 to 6 contain the identifier, residue, sequence, asymmetry
identifier and alternate codes, respectively. These codes may be composed of any characters except an
underscore.
atom_site
Corresponds to the _atom_site_label_component_3 term in the IUCr Core CIF dictionary.
Component 0 is normally a code which matches identically with one of the _atom_type_symbol codes.
If this is the case, then the rules governing the _atom_type_symbol code apply. If, however, the data
item _atom_site_type_symbol is also specified in the atomsite list, component 0 need not match this
symbol or adhere to any of the _atom_type_symbol rules. Component 1 is referred to as the "atom number".
When component 0 is the atomtype code, it is used to number the sites with the same atom type. This
component code must start with at least one digit which is not followed by a + or  sign (to distinguish
it from the component 0 rules). Components 2 to 6 contain the identifier, residue, sequence, asymmetry
identifier and alternate codes, respectively. These codes may be composed of any characters except an
underscore.
atom_site
Corresponds to the _atom_site_label_component_4 term in the IUCr Core CIF dictionary.
Component 0 is normally a code which matches identically with one of the _atom_type_symbol codes.
If this is the case, then the rules governing the _atom_type_symbol code apply. If, however, the data
item _atom_site_type_symbol is also specified in the atomsite list, component 0 need not match this
symbol or adhere to any of the _atom_type_symbol rules. Component 1 is referred to as the "atom number".
When component 0 is the atomtype code, it is used to number the sites with the same atom type. This
component code must start with at least one digit which is not followed by a + or  sign (to distinguish
it from the component 0 rules). Components 2 to 6 contain the identifier, residue, sequence, asymmetry
identifier and alternate codes, respectively. These codes may be composed of any characters except an
underscore.
atom_site
Corresponds to the _atom_site_label_component_5 term in the IUCr Core CIF dictionary.
Component 0 is normally a code which matches identically with one of the _atom_type_symbol codes.
If this is the case, then the rules governing the _atom_type_symbol code apply. If, however, the data
item _atom_site_type_symbol is also specified in the atomsite list, component 0 need not match this
symbol or adhere to any of the _atom_type_symbol rules. Component 1 is referred to as the "atom number".
When component 0 is the atomtype code, it is used to number the sites with the same atom type. This
component code must start with at least one digit which is not followed by a + or  sign (to distinguish
it from the component 0 rules). Components 2 to 6 contain the identifier, residue, sequence, asymmetry
identifier and alternate codes, respectively. These codes may be composed of any characters except an
underscore.
atom_site
Corresponds to the _atom_site_label_component_6 term in the IUCr Core CIF dictionary.
Corresponds to the _atom_site_occupancy term in the IUCr Core CIF dictionary.
The fraction of the atom type present at this site. The sum of the occupancies of all the atom
types at this site may not significantly exceed 1.0 unless it is a dummy site. The value must lie in the
99.97% Gaussian confidence interval 3u =< x =< 1 + 3u. The _enumeration_range of 0.0:1.0 is thus
correctly interpreted as meaning (0.0  3u) =< x =< (1.0 + 3u).
atom_site
Corresponds to the _atom_site_refinement_flags term in the IUCr Core CIF dictionary.
A concatenated series of singleletter codes which indicate the refinement restraints or
constraints applied to this site. This item should not be used. It has been replaced by
_atom_site_refinement_flags_posn, *_adp and *_occupancy. It is retained in this dictionary only to
provide compatibility with legacy CIFs.
atom_site
.
S
G
R
D
T
U
P
Corresponds to the _atom_site_refinement_flags_adp term in the IUCr Core CIF dictionary.
A code which indicates the refinement restraints or constraints applied to the atomic displacement
parameters of this site.
atom_site
.
T
U
TU
Corresponds to the _atom_site_refinement_flags_occupancy term in the IUCr Core CIF dictionary.
A code which indicates that refinement restraints or constraints were applied to the occupancy of
this site.
atom_site
.
P
Corresponds to the _atom_site_refinement_flags_posn term in the IUCr Core CIF dictionary.
A code which indicates the refinement restraints or constraints applied to the positional
coordinates of this site.
atom_site
.
D
G
R
S
DG
DR
DS
GR
GS
RS
DGR
DGS
DRS
GRS
DGRS
Corresponds to the _atom_site_restraints term in the IUCr Core CIF dictionary.
A description of restraints applied to specific parameters at this site during refinement. See also
_atom_site_refinement_flags and _refine_ls_number_restraints.
atom_site
Corresponds to the _atom_site_symmetry_multiplicity term in the IUCr Core CIF dictionary.
The multiplicity of a site due to the spacegroup symmetry as given in International Tables for
Crystallography Vol. A (2002).
atom_site
Corresponds to the _atom_site_thermal_displace_type term in the IUCr Core CIF dictionary.
A standard code used to describe the type of atomic displacement parameters used for the site.
atom_site
Uani
Uiso
Uovl
Umpe
Bani
Biso
Bovl
Corresponds to the _atom_site_type_symbol term in the IUCr Core CIF dictionary.
A code to identify the atom species (singular or plural) occupying this site. This code must match
a corresponding _atom_type_symbol. The specification of this code is optional if component 0 of the
_atom_site_label is used for this purpose. See _atom_type_symbol.
atom_site
Corresponds to the _atom_site_u_equiv_geom_mean term in the IUCr Core CIF dictionary.
Equivalent isotropic atomic displacement parameter, U(equiv), in angstroms squared, calculated as
the geometric mean of the anisotropic atomic displacement parameters. U(equiv) = (U~i~ U~j~ U~k~)^1/3^
U~n~ = the principal components of the orthogonalized U^ij^
atom_site
Corresponds to the _atom_site_u_iso_or_equiv term in the IUCr Core CIF dictionary.
Isotropic atomic displacement parameter, or equivalent isotropic atomic displacement parameter,
U(equiv), in angstroms squared, calculated from anisotropic atomic displacement parameters. U(equiv) =
(1/3) sum~i~[sum~j~(U^ij^ a*~i~ a*~j~ a~i~ a~j~)] a = the realspace cell lengths a* = the
reciprocalspace cell lengths Ref: Fischer, R. X. & Tillmanns, E. (1988). Acta Cryst. C44, 775776.
atom_site
Corresponds to the _atom_site_wyckoff_symbol term in the IUCr Core CIF dictionary.
The Wyckoff symbol (letter) as listed in the spacegroup tables of International Tables for
Crystallography Vol. A (2002).
atom_site
Matrix elements used to transform fractional coordinates in the ATOM_SITE category to Cartesian
coordinates. The axial alignments of this transformation are described in
_atom_sites_Cartn_transform_axes. The 3 x 1 translation is defined in _atom_sites_Cartn_tran_vector_. x'
11 12 13 x  1  ( y' ) Cartesian = 21 22 23 ( y ) fractional +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_cartn_tran_matrix_11 term in the IUCr Core CIF dictionary.
Matrix elements used to transform fractional coordinates in the ATOM_SITE category to Cartesian
coordinates. The axial alignments of this transformation are described in
_atom_sites_Cartn_transform_axes. The 3 x 1 translation is defined in _atom_sites_Cartn_tran_vector_. x'
11 12 13 x  1  ( y' ) Cartesian = 21 22 23 ( y ) fractional +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_cartn_tran_matrix_12 term in the IUCr Core CIF dictionary.
Matrix elements used to transform fractional coordinates in the ATOM_SITE category to Cartesian
coordinates. The axial alignments of this transformation are described in
_atom_sites_Cartn_transform_axes. The 3 x 1 translation is defined in _atom_sites_Cartn_tran_vector_. x'
11 12 13 x  1  ( y' ) Cartesian = 21 22 23 ( y ) fractional +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_cartn_tran_matrix_13 term in the IUCr Core CIF dictionary.
Matrix elements used to transform fractional coordinates in the ATOM_SITE category to Cartesian
coordinates. The axial alignments of this transformation are described in
_atom_sites_Cartn_transform_axes. The 3 x 1 translation is defined in _atom_sites_Cartn_tran_vector_. x'
11 12 13 x  1  ( y' ) Cartesian = 21 22 23 ( y ) fractional +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_cartn_tran_matrix_21 term in the IUCr Core CIF dictionary.
Matrix elements used to transform fractional coordinates in the ATOM_SITE category to Cartesian
coordinates. The axial alignments of this transformation are described in
_atom_sites_Cartn_transform_axes. The 3 x 1 translation is defined in _atom_sites_Cartn_tran_vector_. x'
11 12 13 x  1  ( y' ) Cartesian = 21 22 23 ( y ) fractional +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_cartn_tran_matrix_22 term in the IUCr Core CIF dictionary.
Matrix elements used to transform fractional coordinates in the ATOM_SITE category to Cartesian
coordinates. The axial alignments of this transformation are described in
_atom_sites_Cartn_transform_axes. The 3 x 1 translation is defined in _atom_sites_Cartn_tran_vector_. x'
11 12 13 x  1  ( y' ) Cartesian = 21 22 23 ( y ) fractional +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_cartn_tran_matrix_23 term in the IUCr Core CIF dictionary.
Matrix elements used to transform fractional coordinates in the ATOM_SITE category to Cartesian
coordinates. The axial alignments of this transformation are described in
_atom_sites_Cartn_transform_axes. The 3 x 1 translation is defined in _atom_sites_Cartn_tran_vector_. x'
11 12 13 x  1  ( y' ) Cartesian = 21 22 23 ( y ) fractional +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_cartn_tran_matrix_31 term in the IUCr Core CIF dictionary.
Matrix elements used to transform fractional coordinates in the ATOM_SITE category to Cartesian
coordinates. The axial alignments of this transformation are described in
_atom_sites_Cartn_transform_axes. The 3 x 1 translation is defined in _atom_sites_Cartn_tran_vector_. x'
11 12 13 x  1  ( y' ) Cartesian = 21 22 23 ( y ) fractional +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_cartn_tran_matrix_32 term in the IUCr Core CIF dictionary.
Matrix elements used to transform fractional coordinates in the ATOM_SITE category to Cartesian
coordinates. The axial alignments of this transformation are described in
_atom_sites_Cartn_transform_axes. The 3 x 1 translation is defined in _atom_sites_Cartn_tran_vector_. x'
11 12 13 x  1  ( y' ) Cartesian = 21 22 23 ( y ) fractional +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_cartn_tran_matrix_33 term in the IUCr Core CIF dictionary.
Elements of a 3 x 1 translation vector used in the transformation of fractional coordinates in the
ATOM_SITE category to Cartesian coordinates. The axial alignments of this transformation are described
in _atom_sites_Cartn_transform_axes. x' 11 12 13 x  1  ( y' ) Cartesian = 21 22 23 ( y )
fractional +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_cartn_tran_vector_1 term in the IUCr Core CIF dictionary.
Elements of a 3 x 1 translation vector used in the transformation of fractional coordinates in the
ATOM_SITE category to Cartesian coordinates. The axial alignments of this transformation are described
in _atom_sites_Cartn_transform_axes. x' 11 12 13 x  1  ( y' ) Cartesian = 21 22 23 ( y )
fractional +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_cartn_tran_vector_2 term in the IUCr Core CIF dictionary.
Elements of a 3 x 1 translation vector used in the transformation of fractional coordinates in the
ATOM_SITE category to Cartesian coordinates. The axial alignments of this transformation are described
in _atom_sites_Cartn_transform_axes. x' 11 12 13 x  1  ( y' ) Cartesian = 21 22 23 ( y )
fractional +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_cartn_tran_vector_3 term in the IUCr Core CIF dictionary.
Corresponds to the _atom_sites_cartn_transform_axes term in the IUCr Core CIF dictionary.
A description of the relative alignment of the crystal cell axes to the Cartesian orthogonal axes
as applied in the transformation matrix _atom_sites_Cartn_tran_matrix_.
atom_sites
Matrix elements used to transform Cartesian coordinates in the ATOM_SITE category to fractional
coordinates. The axial alignments of this transformation are described in
_atom_sites_Cartn_transform_axes. The 3 x 1 translation is defined in _atom_sites_fract_tran_vector_. x'
11 12 13 x  1  ( y' ) fractional = 21 22 23 ( y ) Cartesian +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_fract_tran_matrix_11 term in the IUCr Core CIF dictionary.
Matrix elements used to transform Cartesian coordinates in the ATOM_SITE category to fractional
coordinates. The axial alignments of this transformation are described in
_atom_sites_Cartn_transform_axes. The 3 x 1 translation is defined in _atom_sites_fract_tran_vector_. x'
11 12 13 x  1  ( y' ) fractional = 21 22 23 ( y ) Cartesian +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_fract_tran_matrix_12 term in the IUCr Core CIF dictionary.
Matrix elements used to transform Cartesian coordinates in the ATOM_SITE category to fractional
coordinates. The axial alignments of this transformation are described in
_atom_sites_Cartn_transform_axes. The 3 x 1 translation is defined in _atom_sites_fract_tran_vector_. x'
11 12 13 x  1  ( y' ) fractional = 21 22 23 ( y ) Cartesian +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_fract_tran_matrix_13 term in the IUCr Core CIF dictionary.
Matrix elements used to transform Cartesian coordinates in the ATOM_SITE category to fractional
coordinates. The axial alignments of this transformation are described in
_atom_sites_Cartn_transform_axes. The 3 x 1 translation is defined in _atom_sites_fract_tran_vector_. x'
11 12 13 x  1  ( y' ) fractional = 21 22 23 ( y ) Cartesian +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_fract_tran_matrix_21 term in the IUCr Core CIF dictionary.
Matrix elements used to transform Cartesian coordinates in the ATOM_SITE category to fractional
coordinates. The axial alignments of this transformation are described in
_atom_sites_Cartn_transform_axes. The 3 x 1 translation is defined in _atom_sites_fract_tran_vector_. x'
11 12 13 x  1  ( y' ) fractional = 21 22 23 ( y ) Cartesian +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_fract_tran_matrix_22 term in the IUCr Core CIF dictionary.
Matrix elements used to transform Cartesian coordinates in the ATOM_SITE category to fractional
coordinates. The axial alignments of this transformation are described in
_atom_sites_Cartn_transform_axes. The 3 x 1 translation is defined in _atom_sites_fract_tran_vector_. x'
11 12 13 x  1  ( y' ) fractional = 21 22 23 ( y ) Cartesian +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_fract_tran_matrix_23 term in the IUCr Core CIF dictionary.
Matrix elements used to transform Cartesian coordinates in the ATOM_SITE category to fractional
coordinates. The axial alignments of this transformation are described in
_atom_sites_Cartn_transform_axes. The 3 x 1 translation is defined in _atom_sites_fract_tran_vector_. x'
11 12 13 x  1  ( y' ) fractional = 21 22 23 ( y ) Cartesian +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_fract_tran_matrix_31 term in the IUCr Core CIF dictionary.
Matrix elements used to transform Cartesian coordinates in the ATOM_SITE category to fractional
coordinates. The axial alignments of this transformation are described in
_atom_sites_Cartn_transform_axes. The 3 x 1 translation is defined in _atom_sites_fract_tran_vector_. x'
11 12 13 x  1  ( y' ) fractional = 21 22 23 ( y ) Cartesian +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_fract_tran_matrix_32 term in the IUCr Core CIF dictionary.
Matrix elements used to transform Cartesian coordinates in the ATOM_SITE category to fractional
coordinates. The axial alignments of this transformation are described in
_atom_sites_Cartn_transform_axes. The 3 x 1 translation is defined in _atom_sites_fract_tran_vector_. x'
11 12 13 x  1  ( y' ) fractional = 21 22 23 ( y ) Cartesian +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_fract_tran_matrix_33 term in the IUCr Core CIF dictionary.
Elements of a 3 x 1 translation vector used in the transformation of Cartesian coordinates in the
ATOM_SITE category to fractional coordinates. The axial alignments of this transformation are described
in _atom_sites_Cartn_transform_axes. x' 11 12 13 x  1  ( y' ) fractional = 21 22 23 ( y )
Cartesian +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_fract_tran_vector_1 term in the IUCr Core CIF dictionary.
Elements of a 3 x 1 translation vector used in the transformation of Cartesian coordinates in the
ATOM_SITE category to fractional coordinates. The axial alignments of this transformation are described
in _atom_sites_Cartn_transform_axes. x' 11 12 13 x  1  ( y' ) fractional = 21 22 23 ( y )
Cartesian +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_fract_tran_vector_2 term in the IUCr Core CIF dictionary.
Elements of a 3 x 1 translation vector used in the transformation of Cartesian coordinates in the
ATOM_SITE category to fractional coordinates. The axial alignments of this transformation are described
in _atom_sites_Cartn_transform_axes. x' 11 12 13 x  1  ( y' ) fractional = 21 22 23 ( y )
Cartesian +  2  z' 31 32 33 z  3 
atom_sites
Corresponds to the _atom_sites_fract_tran_vector_3 term in the IUCr Core CIF dictionary.
Codes which identify the methods used to locate the initial atom sites. The *_primary code
identifies how the first atom sites were determined; the *_secondary code identifies how the remaining
nonhydrogen sites were located; and the *_hydrogens code identifies how the hydrogen sites were
located. Ref: Sheldrick, G. M., Hauptman, H. A., Weeks, C. M., Miller, R. and Us\'on, I. (2001). Ab
initio phasing. In International Tables for Crystallography, Vol. F. Crystallography of biological
macromolecules, edited by M. G. Rossmann and E. Arnold, ch. 16.1. Dordrecht: Kluwer Academic Publishers.
atom_sites
difmap
vecmap
heavy
direct
geom
disper
isomor
notdet
dual
other
Corresponds to the _atom_sites_solution_primary term in the IUCr Core CIF dictionary.
Codes which identify the methods used to locate the initial atom sites. The *_primary code
identifies how the first atom sites were determined; the *_secondary code identifies how the remaining
nonhydrogen sites were located; and the *_hydrogens code identifies how the hydrogen sites were
located. Ref: Sheldrick, G. M., Hauptman, H. A., Weeks, C. M., Miller, R. and Us\'on, I. (2001). Ab
initio phasing. In International Tables for Crystallography, Vol. F. Crystallography of biological
macromolecules, edited by M. G. Rossmann and E. Arnold, ch. 16.1. Dordrecht: Kluwer Academic Publishers.
atom_sites
difmap
vecmap
heavy
direct
geom
disper
isomor
notdet
dual
other
Corresponds to the _atom_sites_solution_secondary term in the IUCr Core CIF dictionary.
Codes which identify the methods used to locate the initial atom sites. The *_primary code
identifies how the first atom sites were determined; the *_secondary code identifies how the remaining
nonhydrogen sites were located; and the *_hydrogens code identifies how the hydrogen sites were
located. Ref: Sheldrick, G. M., Hauptman, H. A., Weeks, C. M., Miller, R. and Us\'on, I. (2001). Ab
initio phasing. In International Tables for Crystallography, Vol. F. Crystallography of biological
macromolecules, edited by M. G. Rossmann and E. Arnold, ch. 16.1. Dordrecht: Kluwer Academic Publishers.
atom_sites
difmap
vecmap
heavy
direct
geom
disper
isomor
notdet
dual
other
Corresponds to the _atom_sites_solution_hydrogens term in the IUCr Core CIF dictionary.
Corresponds to the _atom_sites_special_details term in the IUCr Core CIF dictionary.
Additional information about the atomic coordinates not coded elsewhere in the CIF.
atom_sites
Corresponds to the _atom_type_analytical_mass_% term in the IUCr Core CIF dictionary.
Mass percentage of this atom type derived from chemical analysis.
atom_type
Corresponds to the _atom_type_description term in the IUCr Core CIF dictionary.
A description of the atom(s) designated by this atom type. In most cases, this will be the element
name and oxidation state of a single atom species. For disordered or nonstoichiometric structures it
will describe a combination of atom species.
atom_type
Corresponds to the _atom_type_number_in_cell term in the IUCr Core CIF dictionary.
Total number of atoms of this atom type in the unit cell.
atom_type
Corresponds to the _atom_type_oxidation_number term in the IUCr Core CIF dictionary.
Formal oxidation state of this atom type in the structure.
atom_type
The effective intra and intermolecular bonding radii in angstroms of this atom type.
atom_type
Corresponds to the _atom_type_radius_bond term in the IUCr Core CIF dictionary.
The effective intra and intermolecular bonding radii in angstroms of this atom type.
atom_type
Corresponds to the _atom_type_radius_contact term in the IUCr Core CIF dictionary.
The CromerMann scatteringfactor coefficients used to calculate the scattering factors for this
atom type. Ref: International Tables for Xray Crystallography (1974). Vol. IV, Table 2.2B or
International Tables for Crystallography (2004). Vol. C, Tables 6.1.1.4 and 6.1.1.5
atom_type
Corresponds to the _atom_type_scat_cromer_mann_a1 term in the IUCr Core CIF dictionary.
The CromerMann scatteringfactor coefficients used to calculate the scattering factors for this
atom type. Ref: International Tables for Xray Crystallography (1974). Vol. IV, Table 2.2B or
International Tables for Crystallography (2004). Vol. C, Tables 6.1.1.4 and 6.1.1.5
atom_type
Corresponds to the _atom_type_scat_cromer_mann_a2 term in the IUCr Core CIF dictionary.
The CromerMann scatteringfactor coefficients used to calculate the scattering factors for this
atom type. Ref: International Tables for Xray Crystallography (1974). Vol. IV, Table 2.2B or
International Tables for Crystallography (2004). Vol. C, Tables 6.1.1.4 and 6.1.1.5
atom_type
Corresponds to the _atom_type_scat_cromer_mann_a3 term in the IUCr Core CIF dictionary.
The CromerMann scatteringfactor coefficients used to calculate the scattering factors for this
atom type. Ref: International Tables for Xray Crystallography (1974). Vol. IV, Table 2.2B or
International Tables for Crystallography (2004). Vol. C, Tables 6.1.1.4 and 6.1.1.5
atom_type
Corresponds to the _atom_type_scat_cromer_mann_a4 term in the IUCr Core CIF dictionary.
The CromerMann scatteringfactor coefficients used to calculate the scattering factors for this
atom type. Ref: International Tables for Xray Crystallography (1974). Vol. IV, Table 2.2B or
International Tables for Crystallography (2004). Vol. C, Tables 6.1.1.4 and 6.1.1.5
atom_type
Corresponds to the _atom_type_scat_cromer_mann_b1 term in the IUCr Core CIF dictionary.
The CromerMann scatteringfactor coefficients used to calculate the scattering factors for this
atom type. Ref: International Tables for Xray Crystallography (1974). Vol. IV, Table 2.2B or
International Tables for Crystallography (2004). Vol. C, Tables 6.1.1.4 and 6.1.1.5
atom_type
Corresponds to the _atom_type_scat_cromer_mann_b2 term in the IUCr Core CIF dictionary.
The CromerMann scatteringfactor coefficients used to calculate the scattering factors for this
atom type. Ref: International Tables for Xray Crystallography (1974). Vol. IV, Table 2.2B or
International Tables for Crystallography (2004). Vol. C, Tables 6.1.1.4 and 6.1.1.5
atom_type
Corresponds to the _atom_type_scat_cromer_mann_b3 term in the IUCr Core CIF dictionary.
The CromerMann scatteringfactor coefficients used to calculate the scattering factors for this
atom type. Ref: International Tables for Xray Crystallography (1974). Vol. IV, Table 2.2B or
International Tables for Crystallography (2004). Vol. C, Tables 6.1.1.4 and 6.1.1.5
atom_type
Corresponds to the _atom_type_scat_cromer_mann_b4 term in the IUCr Core CIF dictionary.
The CromerMann scatteringfactor coefficients used to calculate the scattering factors for this
atom type. Ref: International Tables for Xray Crystallography (1974). Vol. IV, Table 2.2B or
International Tables for Crystallography (2004). Vol. C, Tables 6.1.1.4 and 6.1.1.5
atom_type
Corresponds to the _atom_type_scat_cromer_mann_c term in the IUCr Core CIF dictionary.
The imaginary and real components of the anomalousdispersion scattering factor, f'' and f', in
electrons for this atom type and the radiation given in _diffrn_radiation_wavelength.
atom_type
Corresponds to the _atom_type_scat_dispersion_imag term in the IUCr Core CIF dictionary.
The imaginary and real components of the anomalousdispersion scattering factor, f'' and f', in
electrons for this atom type and the radiation given in _diffrn_radiation_wavelength.
atom_type
Corresponds to the _atom_type_scat_dispersion_real term in the IUCr Core CIF dictionary.
Corresponds to the _atom_type_scat_dispersion_source term in the IUCr Core CIF dictionary.
Reference to source of real and imaginary dispersion corrections for scattering factors used for
this atom type.
atom_type
Corresponds to the _atom_type_scat_length_neutron term in the IUCr Core CIF dictionary.
The bound coherent scattering length in femtometres for the atom type at the isotopic composition
used for the diffraction experiment.
atom_type
Corresponds to the _atom_type_scat_source term in the IUCr Core CIF dictionary.
Reference to source of scattering factors or scattering lengths used for this atom type.
atom_type
Corresponds to the _atom_type_scat_versus_stol_list term in the IUCr Core CIF dictionary.
A table of scattering factors as a function of sin theta over lambda. This table should be well
commented to indicate the items present. Regularly formatted lists are strongly recommended.
atom_type
Corresponds to the _atom_type_symbol term in the IUCr Core CIF dictionary.
The code used to identify the atom species (singular or plural) representing this atom type.
Normally this code is the element symbol. The code may be composed of any character except an underscore
with the additional proviso that digits designate an oxidation state and must be followed by a + or 
character.
atom_type
Corresponds to the _audit_block_code term in the IUCr Core CIF dictionary.
A code intended to identify uniquely the current data block.
audit
Corresponds to the _audit_creation_date term in the IUCr Core CIF dictionary.
The date that the data block was created. The date format is yyyymmdd.
audit
Corresponds to the _audit_creation_method term in the IUCr Core CIF dictionary.
A description of how data were entered into the data block.
audit
Corresponds to the _audit_update_record term in the IUCr Core CIF dictionary.
A record of any changes to the data block. The update format is a date (yyyymmdd) followed by a
description of the changes. The latest update entry is added to the bottom of this record.
audit
Corresponds to the _audit_author_address term in the IUCr Core CIF dictionary.
The address of an author of this data block. If there are multiple authors, _audit_author_address
is looped with _audit_author_name.
audit_author
Corresponds to the _audit_author_name term in the IUCr Core CIF dictionary.
The name of an author of this data block. If there are multiple authors, _audit_author_name is
looped with _audit_author_address. The family name(s), followed by a comma and including any dynastic
components, precedes the first name(s) or initial(s).
audit_author
Corresponds to the _audit_conform_dict_location term in the IUCr Core CIF dictionary.
A file name or uniform resource locator (URL) for the dictionary to which the current data block
conforms.
audit_conform
Corresponds to the _audit_conform_dict_name term in the IUCr Core CIF dictionary.
The string identifying the highestlevel dictionary defining data names used in this file.
audit_conform
Corresponds to the _audit_conform_dict_version term in the IUCr Core CIF dictionary.
The version number of the dictionary to which the current data block conforms.
audit_conform
Corresponds to the _audit_contact_author_address term in the IUCr Core CIF dictionary.
The mailing address of the author of the data block to whom correspondence should be addressed.
audit_contact_author
Corresponds to the _audit_contact_author_email term in the IUCr Core CIF dictionary.
The electronic mail address of the author of the data block to whom correspondence should be
addressed, in a form recognizable to international networks. The format of email addresses is given in
Section 3.4, Address Specification, of Internet Message Format, RFC 2822, P. Resnick (Editor), Network
Standards Group, April 2001.
audit_contact_author
Corresponds to the _audit_contact_author_fax term in the IUCr Core CIF dictionary.
The facsimile telephone number of the author of the data block to whom correspondence should be
addressed. The recommended style starts with the international dialing prefix, followed by the area code
in parentheses, followed by the local number with no spaces.
audit_contact_author
Corresponds to the _audit_contact_author_name term in the IUCr Core CIF dictionary.
The name of the author of the data block to whom correspondence should be addressed. The family
name(s), followed by a comma and including any dynastic components, precedes the first name(s) or
initial(s).
audit_contact_author
Corresponds to the _audit_contact_author_phone term in the IUCr Core CIF dictionary.
The telephone number of the author of the data block to whom correspondence should be addressed.
The recommended style starts with the international dialing prefix, followed by the area code in
parentheses, followed by the local number and any extension number prefixed by 'x', with no spaces.
audit_contact_author
Corresponds to the _audit_link_block_code term in the IUCr Core CIF dictionary.
The value of _audit_block_code associated with a data block in the current file related to the
current data block. The special value '.' may be used to refer to the current data block for
completeness.
audit_link
Corresponds to the _audit_link_block_description term in the IUCr Core CIF dictionary.
A textual description of the relationship of the referenced data block to the current one.
audit_link
Unitcell angles of the reported structure in degrees. The values of _refln_index_h, *_k, *_l must
correspond to the cell defined by these values and _cell_length_a, *_b and *_c. The values of
_diffrn_refln_index_h, *_k, *_l may not correspond to these values if a cell transformation took place
following the measurement of the diffraction intensities. See also _diffrn_reflns_transf_matrix_.
cell
Corresponds to the _cell_angle_alpha term in the IUCr Core CIF dictionary.
Unitcell angles of the reported structure in degrees. The values of _refln_index_h, *_k, *_l must
correspond to the cell defined by these values and _cell_length_a, *_b and *_c. The values of
_diffrn_refln_index_h, *_k, *_l may not correspond to these values if a cell transformation took place
following the measurement of the diffraction intensities. See also _diffrn_reflns_transf_matrix_.
cell
Corresponds to the _cell_angle_beta term in the IUCr Core CIF dictionary.
Unitcell angles of the reported structure in degrees. The values of _refln_index_h, *_k, *_l must
correspond to the cell defined by these values and _cell_length_a, *_b and *_c. The values of
_diffrn_refln_index_h, *_k, *_l may not correspond to these values if a cell transformation took place
following the measurement of the diffraction intensities. See also _diffrn_reflns_transf_matrix_.
cell
Corresponds to the _cell_angle_gamma term in the IUCr Core CIF dictionary.
Corresponds to the _cell_formula_units_z term in the IUCr Core CIF dictionary.
The number of the formula units in the unit cell as specified by _chemical_formula_structural,
_chemical_formula_moiety or _chemical_formula_sum.
cell
Unitcell lengths in angstroms corresponding to the structure reported. The values of
_refln_index_h, *_k, *_l must correspond to the cell defined by these values and _cell_angle_ values.
The values of _diffrn_refln_index_h, *_k, *_l may not correspond to these values if a cell
transformation took place following the measurement of the diffraction intensities. See also
_diffrn_reflns_transf_matrix_.
cell
Corresponds to the _cell_length_a term in the IUCr Core CIF dictionary.
Unitcell lengths in angstroms corresponding to the structure reported. The values of
_refln_index_h, *_k, *_l must correspond to the cell defined by these values and _cell_angle_ values.
The values of _diffrn_refln_index_h, *_k, *_l may not correspond to these values if a cell
transformation took place following the measurement of the diffraction intensities. See also
_diffrn_reflns_transf_matrix_.
cell
Corresponds to the _cell_length_b term in the IUCr Core CIF dictionary.
Unitcell lengths in angstroms corresponding to the structure reported. The values of
_refln_index_h, *_k, *_l must correspond to the cell defined by these values and _cell_angle_ values.
The values of _diffrn_refln_index_h, *_k, *_l may not correspond to these values if a cell
transformation took place following the measurement of the diffraction intensities. See also
_diffrn_reflns_transf_matrix_.
cell
Corresponds to the _cell_length_c term in the IUCr Core CIF dictionary.
Corresponds to the _cell_measurement_pressure term in the IUCr Core CIF dictionary.
The pressure in kilopascals at which the unitcell parameters were measured (not the pressure at
which the sample was synthesized).
cell
Corresponds to the _cell_measurement_radiation term in the IUCr Core CIF dictionary.
Description of the radiation used to measure the unitcell data. See also
_cell_measurement_wavelength.
cell
Corresponds to the _cell_measurement_reflns_used term in the IUCr Core CIF dictionary.
The total number of reflections used to determine the unit cell. These reflections may be specified
as _cell_measurement_refln_ data items.
cell
Corresponds to the _cell_measurement_temperature term in the IUCr Core CIF dictionary.
The temperature in kelvins at which the unitcell parameters were measured (not the temperature of
synthesis).
cell
The maximum and minimum theta angles of reflections used to measure the unit cell in degrees.
cell
Corresponds to the _cell_measurement_theta_max term in the IUCr Core CIF dictionary.
The maximum and minimum theta angles of reflections used to measure the unit cell in degrees.
cell
Corresponds to the _cell_measurement_theta_min term in the IUCr Core CIF dictionary.
Corresponds to the _cell_measurement_wavelength term in the IUCr Core CIF dictionary.
The wavelength in angstroms of the radiation used to measure the unit cell. If this is not
specified, the wavelength is assumed to be the same as that given in _diffrn_radiation_wavelength.
cell
The angles defining the reciprocal cell in degrees. These are related to those in the real cell by:
cos(recipalpha) = [cos(beta)*cos(gamma)  cos(alpha)]/[sin(beta)*sin(gamma)] cos(recipbeta) =
[cos(gamma)*cos(alpha)  cos(beta)]/[sin(gamma)*sin(alpha)] cos(recipgamma) = [cos(alpha)*cos(beta) 
cos(gamma)]/[sin(alpha)*sin(beta)] Ref: Buerger, M. J. (1942). Xray Crystallography, p. 360. New York:
John Wiley & Sons Inc.
cell
Corresponds to the _cell_reciprocal_angle_alpha term in the IUCr Core CIF dictionary.
The angles defining the reciprocal cell in degrees. These are related to those in the real cell by:
cos(recipalpha) = [cos(beta)*cos(gamma)  cos(alpha)]/[sin(beta)*sin(gamma)] cos(recipbeta) =
[cos(gamma)*cos(alpha)  cos(beta)]/[sin(gamma)*sin(alpha)] cos(recipgamma) = [cos(alpha)*cos(beta) 
cos(gamma)]/[sin(alpha)*sin(beta)] Ref: Buerger, M. J. (1942). Xray Crystallography, p. 360. New York:
John Wiley & Sons Inc.
cell
Corresponds to the _cell_reciprocal_angle_beta term in the IUCr Core CIF dictionary.
The angles defining the reciprocal cell in degrees. These are related to those in the real cell by:
cos(recipalpha) = [cos(beta)*cos(gamma)  cos(alpha)]/[sin(beta)*sin(gamma)] cos(recipbeta) =
[cos(gamma)*cos(alpha)  cos(beta)]/[sin(gamma)*sin(alpha)] cos(recipgamma) = [cos(alpha)*cos(beta) 
cos(gamma)]/[sin(alpha)*sin(beta)] Ref: Buerger, M. J. (1942). Xray Crystallography, p. 360. New York:
John Wiley & Sons Inc.
cell
Corresponds to the _cell_reciprocal_angle_gamma term in the IUCr Core CIF dictionary.
The reciprocalcell lengths in inverse angstroms. These are related to the real cell by: recipa =
b*c*sin(alpha)/V recipb = c*a*sin(beta)/V recipc = a*b*sin(gamma)/V where V is the cell volume. Ref:
Buerger, M. J. (1942). Xray Crystallography, p. 360. New York: John Wiley & Sons Inc.
cell
Corresponds to the _cell_reciprocal_length_a term in the IUCr Core CIF dictionary.
The reciprocalcell lengths in inverse angstroms. These are related to the real cell by: recipa =
b*c*sin(alpha)/V recipb = c*a*sin(beta)/V recipc = a*b*sin(gamma)/V where V is the cell volume. Ref:
Buerger, M. J. (1942). Xray Crystallography, p. 360. New York: John Wiley & Sons Inc.
cell
Corresponds to the _cell_reciprocal_length_b term in the IUCr Core CIF dictionary.
The reciprocalcell lengths in inverse angstroms. These are related to the real cell by: recipa =
b*c*sin(alpha)/V recipb = c*a*sin(beta)/V recipc = a*b*sin(gamma)/V where V is the cell volume. Ref:
Buerger, M. J. (1942). Xray Crystallography, p. 360. New York: John Wiley & Sons Inc.
cell
Corresponds to the _cell_reciprocal_length_c term in the IUCr Core CIF dictionary.
Corresponds to the _cell_special_details term in the IUCr Core CIF dictionary.
A description of special aspects of the cell choice, noting possible alternative settings.
cell
Corresponds to the _cell_volume term in the IUCr Core CIF dictionary.
Cell volume V in angstroms cubed. V = a b c [1  cos^2^(alpha)  cos^2^(beta)  cos^2^(gamma) + 2
cos(alpha) cos(beta) cos(gamma) ] ^1/2^ a = _cell_length_a b = _cell_length_b c = _cell_length_c alpha =
_cell_angle_alpha beta = _cell_angle_beta gamma = _cell_angle_gamma
cell
Miller indices of a reflection used for measurement of the unit cell.
cell_measurement_refln
Corresponds to the _cell_measurement_refln_index_h term in the IUCr Core CIF dictionary.
Miller indices of a reflection used for measurement of the unit cell.
cell_measurement_refln
Corresponds to the _cell_measurement_refln_index_k term in the IUCr Core CIF dictionary.
Miller indices of a reflection used for measurement of the unit cell.
cell_measurement_refln
Corresponds to the _cell_measurement_refln_index_l term in the IUCr Core CIF dictionary.
Corresponds to the _cell_measurement_refln_theta term in the IUCr Core CIF dictionary.
Theta angle in degrees for the reflection used for measurement of the unit cell with the indices
_cell_measurement_refln_index_.
cell_measurement_refln
Corresponds to the _chemical_absolute_configuration term in the IUCr Core CIF dictionary.
Necessary conditions for the assignment of _chemical_absolute_configuration are given by H. D.
Flack and G. Bernardinelli (1999, 2000). Ref: Flack, H. D. & Bernardinelli, G. (1999). Acta Cryst.
A55, 908915. (http://www.iucr.org/paper?sh0129) Flack, H. D. & Bernardinelli, G. (2000). J. Appl.
Cryst. 33, 11431148. (http://www.iucr.org/paper?ks0021)
chemical
rm
ad
rmad
syn
unk
.
Corresponds to the _chemical_compound_source term in the IUCr Core CIF dictionary.
Description of the source of the compound under study, or of the parent molecule if a simple
derivative is studied. This includes the place of discovery for minerals or the actual source of a
natural product.
chemical
Corresponds to the _chemical_enantioexcess_bulk term in the IUCr Core CIF dictionary.
The enantioexcess of the bulk material from which the crystals were grown. A value of 0.0 indicates
the racemate. A value of 1.0 indicates that the compound is enantiomerically pure. Enantioexcess is
defined in the IUPAC Recommendations (Moss et al., 1996). The composition of the crystal and bulk must
be the same. Ref: Moss G. P. et al. (1996). Basic Terminology of Stereochemistry. Pure Appl. Chem., 68,
21932222. http://www.chem.qmul.ac.uk/iupac/stereo/index.html
chemical
Corresponds to the _chemical_enantioexcess_bulk_technique term in the IUCr Core CIF dictionary.
The experimental technique used to determine the enantioexcess of the bulk compound.
chemical
OA
CD
EC
other
Corresponds to the _chemical_enantioexcess_crystal term in the IUCr Core CIF dictionary.
The enantioexcess of the crystal used for the diffraction study. A value of 0.0 indicates the
racemate. A value of 1.0 indicates that the crystal is enantiomerically pure. Enantioexcess is defined
in the IUPAC Recommendations (Moss et al., 1996). Ref: Moss G. P. et al. (1996). Basic Terminology of
Stereochemistry. Pure Appl. Chem., 68, 21932222. http://www.chem.qmul.ac.uk/iupac/stereo/index.html
chemical
Corresponds to the _chemical_enantioexcess_crystal_technique term in the IUCr Core CIF dictionary.
The experimental technique used to determine the enantioexcess of the crystal.
chemical
CD
EC
other
Corresponds to the _chemical_melting_point term in the IUCr Core CIF dictionary.
The temperature in kelvins at which the crystalline solid changes to a liquid.
chemical
A temperature in kelvins below which (*_lt) or above which (*_gt) the melting point (the
temperature at which the crystalline solid changes to a liquid) lies. These items allow a range of
temperatures to be given. _chemical_melting_point should always be used in preference to these items
whenever possible.
chemical
Corresponds to the _chemical_melting_point_gt term in the IUCr Core CIF dictionary.
A temperature in kelvins below which (*_lt) or above which (*_gt) the melting point (the
temperature at which the crystalline solid changes to a liquid) lies. These items allow a range of
temperatures to be given. _chemical_melting_point should always be used in preference to these items
whenever possible.
chemical
Corresponds to the _chemical_melting_point_lt term in the IUCr Core CIF dictionary.
Corresponds to the _chemical_name_common term in the IUCr Core CIF dictionary.
Trivial name by which the compound is commonly known.
chemical
Corresponds to the _chemical_name_mineral term in the IUCr Core CIF dictionary.
Mineral name accepted by the International Mineralogical Association. Use only for natural
minerals. See also _chemical_compound_source.
chemical
Corresponds to the _chemical_name_structure_type term in the IUCr Core CIF dictionary.
Commonly used structuretype name. Usually only applied to minerals or inorganic compounds.
chemical
Corresponds to the _chemical_name_systematic term in the IUCr Core CIF dictionary.
IUPAC or Chemical Abstracts full name of the compound.
chemical
Corresponds to the _chemical_optical_rotation term in the IUCr Core CIF dictionary.
The optical rotation in solution of the compound is specified in the following format:
'[\a]^TEMP^~WAVE~ = SORT (c = CONC, SOLV)' where: TEMP is the temperature of the measurement in degrees
Celsius, WAVE is an indication of the wavelength of the light used for the measurement, CONC is the
concentration of the solution given as the mass of the substance in g per 100 ml of solution, SORT is
the signed value (preceded by a + or a  sign) of 100.\a/(l.c), where \a is the signed optical rotation
in degrees measured in a cell of length l in dm and c is the value of CONC as defined above, and SOLV is
the chemical formula of the solvent.
chemical
Corresponds to the _chemical_properties_biological term in the IUCr Core CIF dictionary.
A freetext description of the biological properties of the material.
chemical
Corresponds to the _chemical_properties_physical term in the IUCr Core CIF dictionary.
A freetext description of the physical properties of the material.
chemical
Corresponds to the _chemical_temperature_decomposition term in the IUCr Core CIF dictionary.
The temperature in kelvins at which the solid decomposes.
chemical
A temperature in kelvins below which (*_lt) or above which (*_gt) the solid is known to decompose.
These items allow a range of temperatures to be given. _chemical_temperature_decomposition should always
be used in preference to these items whenever possible.
chemical
Corresponds to the _chemical_temperature_decomposition_gt term in the IUCr Core CIF dictionary.
A temperature in kelvins below which (*_lt) or above which (*_gt) the solid is known to decompose.
These items allow a range of temperatures to be given. _chemical_temperature_decomposition should always
be used in preference to these items whenever possible.
chemical
Corresponds to the _chemical_temperature_decomposition_lt term in the IUCr Core CIF dictionary.
Corresponds to the _chemical_temperature_sublimation term in the IUCr Core CIF dictionary.
The temperature in kelvins at which the solid sublimes.
chemical
A temperature in kelvins below which (*_lt) or above which (*_gt) the solid is known to sublime.
These items allow a range of temperatures to be given. _chemical_temperature_sublimation should always
be used in preference to these items whenever possible.
chemical
Corresponds to the _chemical_temperature_sublimation_gt term in the IUCr Core CIF dictionary.
A temperature in kelvins below which (*_lt) or above which (*_gt) the solid is known to sublime.
These items allow a range of temperatures to be given. _chemical_temperature_sublimation should always
be used in preference to these items whenever possible.
chemical
Corresponds to the _chemical_temperature_sublimation_lt term in the IUCr Core CIF dictionary.
Corresponds to the _chemical_conn_atom_charge term in the IUCr Core CIF dictionary.
The net integer charge assigned to this atom. This is the formal charge assignment normally found
in chemical diagrams.
chemical_conn_atom
The 2D Cartesian coordinates (x,y) of the position of this atom in a recognizable chemical diagram.
The coordinate origin is at the lower left corner, the x axis is horizontal and the y axis is vertical.
The coordinates must lie in the range 0.0 to 1.0. These coordinates can be obtained from projections of
a suitable uncluttered view of the molecular structure.
chemical_conn_atom
Corresponds to the _chemical_conn_atom_display_x term in the IUCr Core CIF dictionary.
The 2D Cartesian coordinates (x,y) of the position of this atom in a recognizable chemical diagram.
The coordinate origin is at the lower left corner, the x axis is horizontal and the y axis is vertical.
The coordinates must lie in the range 0.0 to 1.0. These coordinates can be obtained from projections of
a suitable uncluttered view of the molecular structure.
chemical_conn_atom
Corresponds to the _chemical_conn_atom_display_y term in the IUCr Core CIF dictionary.
Corresponds to the _chemical_conn_atom_nca term in the IUCr Core CIF dictionary.
The number of connected atoms excluding terminal hydrogen atoms.
chemical_conn_atom
Corresponds to the _chemical_conn_atom_nh term in the IUCr Core CIF dictionary.
The total number of hydrogen atoms attached to this atom, regardless of whether they are included
in the refinement or the _atom_site_ list. This number will be the same as _atom_site_attached_hydrogens
only if none of the hydrogen atoms appear in the _atom_site_ list.
chemical_conn_atom
Corresponds to the _chemical_conn_atom_number term in the IUCr Core CIF dictionary.
The chemical sequence number to be associated with this atom.
chemical_conn_atom
Corresponds to the _chemical_conn_atom_type_symbol term in the IUCr Core CIF dictionary.
A code identifying the atom type. This code must match an _atom_type_symbol code in the _atom_type_
list or be a recognizable element symbol.
chemical_conn_atom
Atom numbers which must match with chemical sequence numbers specified as
_chemical_conn_atom_number values. These link the bond connection to the chemical numbering and atom
sites.
chemical_conn_bond
Corresponds to the _chemical_conn_bond_atom_1 term in the IUCr Core CIF dictionary.
Atom numbers which must match with chemical sequence numbers specified as
_chemical_conn_atom_number values. These link the bond connection to the chemical numbering and atom
sites.
chemical_conn_bond
Corresponds to the _chemical_conn_bond_atom_2 term in the IUCr Core CIF dictionary.
Corresponds to the _chemical_conn_bond_type term in the IUCr Core CIF dictionary.
The chemical bond type associated with the connection between the two sites
_chemical_conn_bond_atom_1 and *_2.
chemical_conn_bond
sing
doub
trip
quad
arom
poly
delo
pi
Corresponds to the _chemical_formula_analytical term in the IUCr Core CIF dictionary.
Formula determined by standard chemical analysis including trace elements. See the
_chemical_formula_[] category description for rules for writing chemical formulae. Parentheses are used
only for standard uncertainties (e.s.d.'s).
chemical_formula
Corresponds to the _chemical_formula_iupac term in the IUCr Core CIF dictionary.
Formula expressed in conformance with IUPAC rules for inorganic and metalorganic compounds where
these conflict with the rules for any other _chemical_formula_ entries. Typically used for formatting a
formula in accordance with journal rules. This should appear in the data block in addition to the most
appropriate of the other _chemical_formula_ data names. Ref: IUPAC (1990). Nomenclature of Inorganic
Chemistry. Oxford: Blackwell Scientific Publications.
chemical_formula
Corresponds to the _chemical_formula_moiety term in the IUCr Core CIF dictionary.
Formula with each discrete bonded residue or ion shown as a separate moiety. See the
_chemical_formula_[] category description for rules for writing chemical formulae. In addition to the
general formulae requirements, the following rules apply: (1) Moieties are separated by commas ','. (2)
The order of elements within a moiety follows general rule (5) in the _chemical_formula_[] category
description. (3) Parentheses are not used within moieties but may surround a moiety. Parentheses may not
be nested. (4) Charges should be placed at the end of the moiety. The charge '+' or '' may be preceded
by a numerical multiplier and should be separated from the last (element symbol + count) by a space.
Pre or postmultipliers may be used for individual moieties.
chemical_formula
Corresponds to the _chemical_formula_structural term in the IUCr Core CIF dictionary.
See the _chemical_formula_[] category description for the rules for writing chemical formulae for
inorganics, organometallics, metal complexes etc., in which bonded groups are preserved as discrete
entities within parentheses, with postmultipliers as required. The order of the elements should give as
much information as possible about the chemical structure. Parentheses may be used and nested as
required. This formula should correspond to the structure as actually reported, i.e. trace elements not
included in atomtype and atomsite lists should not be included in this formula (see also
_chemical_formula_analytical).
chemical_formula
Corresponds to the _chemical_formula_sum term in the IUCr Core CIF dictionary.
See the _chemical_formula_[] category description for the rules for writing chemical formulae in
which all discrete bonded residues and ions are summed over the constituent elements, following the
ordering given in general rule (5) in the _chemical_formula_[] category description. Parentheses are not
normally used.
chemical_formula
Corresponds to the _chemical_formula_weight term in the IUCr Core CIF dictionary.
Formula mass in daltons. This mass should correspond to the formulae given under
_chemical_formula_structural, *_iupac, *_moiety or *_sum and, together with the Z value and cell
parameters, should yield the density given as _exptl_crystal_density_diffrn.
chemical_formula
Corresponds to the _chemical_formula_weight_meas term in the IUCr Core CIF dictionary.
Formula mass in daltons measured by a nondiffraction experiment.
chemical_formula
Corresponds to the _citation_abstract term in the IUCr Core CIF dictionary.
Abstract for the citation. This is used most when the citation is extracted from a bibliographic
database that contains full text or abstract information.
citation
Corresponds to the _citation_abstract_id_cas term in the IUCr Core CIF dictionary.
The Chemical Abstracts Service (CAS) abstract identifier; relevant for journal articles.
citation
Corresponds to the _citation_book_id_isbn term in the IUCr Core CIF dictionary.
The International Standard Book Number (ISBN) code assigned to the book cited; relevant for books
or book chapters.
citation
Corresponds to the _citation_book_publisher term in the IUCr Core CIF dictionary.
The name of the publisher of the citation; relevant for books or book chapters.
citation
Corresponds to the _citation_book_publisher_city term in the IUCr Core CIF dictionary.
The location of the publisher of the citation; relevant for books or book chapters.
citation
Corresponds to the _citation_book_title term in the IUCr Core CIF dictionary.
The title of the book in which the citation appeared; relevant for books or book chapters.
citation
Corresponds to the _citation_coordinate_linkage term in the IUCr Core CIF dictionary.
_citation_coordinate_linkage states whether or not this citation is concerned with precisely the
set of coordinates given in the data block. If, for instance, the publication described the same
structure, but the coordinates had undergone further refinement prior to creation of the data block, the
value of this data item would be 'no'.
citation
no
n
yes
y
Corresponds to the _citation_country term in the IUCr Core CIF dictionary.
The country of publication; relevant for books and book chapters.
citation
Corresponds to the _citation_database_id_csd term in the IUCr Core CIF dictionary.
Identifier ('refcode') of the database record in the Cambridge Structural Database that contains
details of the cited structure.
citation
Corresponds to the _citation_database_id_medline term in the IUCr Core CIF dictionary.
Accession number used by Medline to categorize a specific bibliographic entry.
citation
Corresponds to the _citation_id term in the IUCr Core CIF dictionary.
The value of _citation_id must uniquely identify a record in the _citation_ list. The _citation_id
'primary' should be used to indicate the citation that the author(s) consider to be the most pertinent
to the contents of the data block. Note that this item need not be a number; it can be any unique
identifier.
citation
Corresponds to the _citation_journal_abbrev term in the IUCr Core CIF dictionary.
Abbreviated name of the journal cited as given in the Chemical Abstracts Service Source Index.
citation
Corresponds to the _citation_journal_full term in the IUCr Core CIF dictionary.
Full name of the journal cited; relevant for journal articles.
citation
Corresponds to the _citation_journal_id_astm term in the IUCr Core CIF dictionary.
The American Society for Testing and Materials (ASTM) code assigned to the journal cited (also
referred to as the CODEN designator of the Chemical Abstracts Service); relevant for journal articles.
citation
Corresponds to the _citation_journal_id_csd term in the IUCr Core CIF dictionary.
The Cambridge Structural Database (CSD) code assigned to the journal cited; relevant for journal
articles. This is also the system used at the Protein Data Bank (PDB).
citation
Corresponds to the _citation_journal_id_issn term in the IUCr Core CIF dictionary.
The International Standard Serial Number (ISSN) code assigned to the journal cited; relevant for
journal articles.
citation
Corresponds to the _citation_journal_issue term in the IUCr Core CIF dictionary.
Issue number of the journal cited; relevant for journal articles.
citation
Corresponds to the _citation_journal_volume term in the IUCr Core CIF dictionary.
Volume number of the journal cited; relevant for journal articles.
citation
Corresponds to the _citation_language term in the IUCr Core CIF dictionary.
Language in which the cited article is written.
citation
The first and last pages of the citation; relevant for journal articles, books and book chapters.
citation
Corresponds to the _citation_page_first term in the IUCr Core CIF dictionary.
The first and last pages of the citation; relevant for journal articles, books and book chapters.
citation
Corresponds to the _citation_page_last term in the IUCr Core CIF dictionary.
Corresponds to the _citation_special_details term in the IUCr Core CIF dictionary.
A description of special aspects of the relationship of the contents of the data block to the
literature item cited.
citation
Corresponds to the _citation_title term in the IUCr Core CIF dictionary.
The title of the citation; relevant for journal articles, books and book chapters.
citation
Corresponds to the _citation_year term in the IUCr Core CIF dictionary.
The year of the citation; relevant for journal articles, books and book chapters.
citation
Corresponds to the _citation_author_citation_id term in the IUCr Core CIF dictionary.
The value of _citation_author_citation_id must match an identifier specified by _citation_id in the
_citation_ list.
citation_author
Corresponds to the _citation_author_name term in the IUCr Core CIF dictionary.
Name of an author of the citation; relevant for journal articles, books and book chapters. The
family name(s), followed by a comma and including any dynastic components, precedes the first name(s) or
initial(s).
citation_author
Corresponds to the _citation_author_ordinal term in the IUCr Core CIF dictionary.
This data name defines the order of the author's name in the list of authors of a citation.
citation_author
Corresponds to the _citation_editor_citation_id term in the IUCr Core CIF dictionary.
The value of _citation_editor_citation_id must match an identifier specified by _citation_id in the
_citation_ list.
citation_editor
Corresponds to the _citation_editor_name term in the IUCr Core CIF dictionary.
Name of an editor of the citation; relevant for books and book chapters. The family name(s),
followed by a comma and including any dynastic components, precedes the first name(s) or initial(s).
citation_editor
Corresponds to the _citation_editor_ordinal term in the IUCr Core CIF dictionary.
This data name defines the order of the editor's name in the list of editors of a citation.
citation_editor
Software used in the processing of the data. Give the program or package name and a brief
reference.
computing
Corresponds to the _computing_cell_refinement term in the IUCr Core CIF dictionary.
Software used in the processing of the data. Give the program or package name and a brief
reference.
computing
Corresponds to the _computing_data_collection term in the IUCr Core CIF dictionary.
Software used in the processing of the data. Give the program or package name and a brief
reference.
computing
Corresponds to the _computing_data_reduction term in the IUCr Core CIF dictionary.
Software used in the processing of the data. Give the program or package name and a brief
reference.
computing
Corresponds to the _computing_molecular_graphics term in the IUCr Core CIF dictionary.
Software used in the processing of the data. Give the program or package name and a brief
reference.
computing
Corresponds to the _computing_publication_material term in the IUCr Core CIF dictionary.
Software used in the processing of the data. Give the program or package name and a brief
reference.
computing
Corresponds to the _computing_structure_refinement term in the IUCr Core CIF dictionary.
Software used in the processing of the data. Give the program or package name and a brief
reference.
computing
Corresponds to the _computing_structure_solution term in the IUCr Core CIF dictionary.
The codes are assigned by databases: Chemical Abstracts; Cambridge Structural Database (organic and
metalorganic compounds); Inorganic Crystal Structure Database; Metals Data File (metal structures); NBS
(NIST) Crystal Data Database (lattice parameters); Protein Data Bank; and the Powder Diffraction File
(JCPDS/ICDD).
database
Corresponds to the _database_code_cas term in the IUCr Core CIF dictionary.
The codes are assigned by databases: Chemical Abstracts; Cambridge Structural Database (organic and
metalorganic compounds); Inorganic Crystal Structure Database; Metals Data File (metal structures); NBS
(NIST) Crystal Data Database (lattice parameters); Protein Data Bank; and the Powder Diffraction File
(JCPDS/ICDD).
database
Corresponds to the _database_code_csd term in the IUCr Core CIF dictionary.
The codes are assigned by databases: Chemical Abstracts; Cambridge Structural Database (organic and
metalorganic compounds); Inorganic Crystal Structure Database; Metals Data File (metal structures); NBS
(NIST) Crystal Data Database (lattice parameters); Protein Data Bank; and the Powder Diffraction File
(JCPDS/ICDD).
database
Corresponds to the _database_code_icsd term in the IUCr Core CIF dictionary.
The codes are assigned by databases: Chemical Abstracts; Cambridge Structural Database (organic and
metalorganic compounds); Inorganic Crystal Structure Database; Metals Data File (metal structures); NBS
(NIST) Crystal Data Database (lattice parameters); Protein Data Bank; and the Powder Diffraction File
(JCPDS/ICDD).
database
Corresponds to the _database_code_mdf term in the IUCr Core CIF dictionary.
The codes are assigned by databases: Chemical Abstracts; Cambridge Structural Database (organic and
metalorganic compounds); Inorganic Crystal Structure Database; Metals Data File (metal structures); NBS
(NIST) Crystal Data Database (lattice parameters); Protein Data Bank; and the Powder Diffraction File
(JCPDS/ICDD).
database
Corresponds to the _database_code_nbs term in the IUCr Core CIF dictionary.
The codes are assigned by databases: Chemical Abstracts; Cambridge Structural Database (organic and
metalorganic compounds); Inorganic Crystal Structure Database; Metals Data File (metal structures); NBS
(NIST) Crystal Data Database (lattice parameters); Protein Data Bank; and the Powder Diffraction File
(JCPDS/ICDD).
database
Corresponds to the _database_code_pdb term in the IUCr Core CIF dictionary.
The codes are assigned by databases: Chemical Abstracts; Cambridge Structural Database (organic and
metalorganic compounds); Inorganic Crystal Structure Database; Metals Data File (metal structures); NBS
(NIST) Crystal Data Database (lattice parameters); Protein Data Bank; and the Powder Diffraction File
(JCPDS/ICDD).
database
Corresponds to the _database_code_pdf term in the IUCr Core CIF dictionary.
Corresponds to the _database_code_depnum_ccdc_archive term in the IUCr Core CIF dictionary.
Deposition numbers assigned by the Cambridge Crystallographic Data Centre (CCDC) to files
containing structural information archived by the CCDC.
database
Corresponds to the _database_code_depnum_ccdc_fiz term in the IUCr Core CIF dictionary.
Deposition numbers assigned by the Fachinformationszentrum Karlsruhe (FIZ) to files containing
structural information archived by the Cambridge Crystallographic Data Centre (CCDC).
database
Corresponds to the _database_code_depnum_ccdc_journal term in the IUCr Core CIF dictionary.
Deposition numbers assigned by various journals to files containing structural information archived
by the Cambridge Crystallographic Data Centre (CCDC).
database
Corresponds to the _database_csd_history term in the IUCr Core CIF dictionary.
A history of changes made by the Cambridge Crystallographic Data Centre and incorporated into the
Cambridge Structural Database (CSD).
database
The ASTM CODEN designator for a journal as given in the Chemical Source List maintained by the
Chemical Abstracts Service, and the journal code used in the Cambridge Structural Database.
database
Corresponds to the _database_journal_astm term in the IUCr Core CIF dictionary.
The ASTM CODEN designator for a journal as given in the Chemical Source List maintained by the
Chemical Abstracts Service, and the journal code used in the Cambridge Structural Database.
database
Corresponds to the _database_journal_csd term in the IUCr Core CIF dictionary.
Corresponds to the _diffrn_ambient_environment term in the IUCr Core CIF dictionary.
The gas or liquid surrounding the sample, if not air.
diffrn
Corresponds to the _diffrn_ambient_pressure term in the IUCr Core CIF dictionary.
The mean hydrostatic pressure in kilopascals at which the intensities were measured.
diffrn
The mean hydrostatic pressure in kilopascals above which (*_gt) or below which (*_lt) the
intensities were measured. These items allow for a pressure range to be given. _diffrn_ambient_pressure
should always be used in preference to these items whenever possible.
diffrn
Corresponds to the _diffrn_ambient_pressure_gt term in the IUCr Core CIF dictionary.
The mean hydrostatic pressure in kilopascals above which (*_gt) or below which (*_lt) the
intensities were measured. These items allow for a pressure range to be given. _diffrn_ambient_pressure
should always be used in preference to these items whenever possible.
diffrn
Corresponds to the _diffrn_ambient_pressure_lt term in the IUCr Core CIF dictionary.
Corresponds to the _diffrn_ambient_temperature term in the IUCr Core CIF dictionary.
The mean temperature in kelvins at which the intensities were measured.
diffrn
The mean temperature in kelvins above which (*_gt) or below which (*_lt) the intensities were
measured. These items allow a range of temperatures to be given. _diffrn_ambient_temperature should
always be used in preference to these items whenever possible.
diffrn
Corresponds to the _diffrn_ambient_temperature_gt term in the IUCr Core CIF dictionary.
The mean temperature in kelvins above which (*_gt) or below which (*_lt) the intensities were
measured. These items allow a range of temperatures to be given. _diffrn_ambient_temperature should
always be used in preference to these items whenever possible.
diffrn
Corresponds to the _diffrn_ambient_temperature_lt term in the IUCr Core CIF dictionary.
Corresponds to the _diffrn_crystal_treatment term in the IUCr Core CIF dictionary.
Remarks about how the crystal was treated prior to the intensity measurements. Particularly
relevant when intensities were measured at low temperature.
diffrn
Corresponds to the _diffrn_measured_fraction_theta_full term in the IUCr Core CIF dictionary.
Fraction of unique (symmetryindependent) reflections measured out to _diffrn_reflns_theta_full.
diffrn
Corresponds to the _diffrn_measured_fraction_theta_max term in the IUCr Core CIF dictionary.
Fraction of unique (symmetryindependent) reflections measured out to _diffrn_reflns_theta_max.
diffrn
Corresponds to the _diffrn_special_details term in the IUCr Core CIF dictionary.
Special details of the intensitymeasurement process. Should include information about source
instability, crystal motion, degradation and so on.
diffrn
Corresponds to the _diffrn_symmetry_description term in the IUCr Core CIF dictionary.
Observed diffraction point symmetry, systematic absences and possible space group(s) or superspace
group(s) compatible with these.
diffrn
Corresponds to the _diffrn_attenuator_code term in the IUCr Core CIF dictionary.
A code associated with a particular attenuator setting. This code is referenced by the
_diffrn_refln_attenuator_code which is stored with the intensities. See _diffrn_attenuator_scale.
diffrn_attenuator
Corresponds to the _diffrn_attenuator_material term in the IUCr Core CIF dictionary.
Material from which the attenuator is made.
diffrn_attenuator
Corresponds to the _diffrn_attenuator_scale term in the IUCr Core CIF dictionary.
The scale factor applied when an intensity measurement is reduced by an attenuator identified by
_diffrn_attenuator_code. The measured intensity must be multiplied by this scale to convert it to the
same scale as unattenuated intensities.
diffrn_attenuator
Corresponds to the _diffrn_detector term in the IUCr Core CIF dictionary.
The general class of the radiation detector.
diffrn_detector
Corresponds to the _diffrn_detector_area_resol_mean term in the IUCr Core CIF dictionary.
The resolution of an area detector, in pixels/mm.
diffrn_detector
Corresponds to the _diffrn_detector_details term in the IUCr Core CIF dictionary.
A description of special aspects of the radiation detector.
diffrn_detector
Corresponds to the _diffrn_detector_dtime term in the IUCr Core CIF dictionary.
The deadtime in microseconds of the detector used to measure the diffraction intensities.
diffrn_detector
Corresponds to the _diffrn_detector_type term in the IUCr Core CIF dictionary.
The make, model or name of the detector device used.
diffrn_detector
Corresponds to the _diffrn_radiation_detector term in the IUCr Core CIF dictionary.
The detector used to measure the diffraction intensities.
diffrn_detector
Corresponds to the _diffrn_radiation_detector_dtime term in the IUCr Core CIF dictionary.
The deadtime in microseconds of the detector used to measure the diffraction intensities.
diffrn_detector
Corresponds to the _diffrn_measurement_details term in the IUCr Core CIF dictionary.
A description of special aspects of the intensity measurement.
diffrn_measurement
Corresponds to the _diffrn_measurement_device term in the IUCr Core CIF dictionary.
The general class of goniometer or device used to support and orient the specimen.
diffrn_measurement
Corresponds to the _diffrn_measurement_device_details term in the IUCr Core CIF dictionary.
A description of special aspects of the device used to measure the diffraction intensities.
diffrn_measurement
Corresponds to the _diffrn_measurement_device_type term in the IUCr Core CIF dictionary.
The make, model or name of the measurement device (goniometer) used.
diffrn_measurement
Corresponds to the _diffrn_measurement_method term in the IUCr Core CIF dictionary.
Method used to measure the intensities.
diffrn_measurement
Corresponds to the _diffrn_measurement_specimen_support term in the IUCr Core CIF dictionary.
The physical device used to support the crystal during data collection.
diffrn_measurement
Corresponds to the _diffrn_orient_matrix_type term in the IUCr Core CIF dictionary.
A description of the orientation matrix type and how it should be applied to define the orientation
of the crystal precisely with respect to the diffractometer axes.
diffrn_orient_matrix
The elements of the diffractometer orientation matrix. These define the dimensions of the
reciprocal cell and its orientation to the local diffractometer axes. See _diffrn_orient_matrix_type.
diffrn_orient_matrix
Corresponds to the _diffrn_orient_matrix_ub_11 term in the IUCr Core CIF dictionary.
The elements of the diffractometer orientation matrix. These define the dimensions of the
reciprocal cell and its orientation to the local diffractometer axes. See _diffrn_orient_matrix_type.
diffrn_orient_matrix
Corresponds to the _diffrn_orient_matrix_ub_12 term in the IUCr Core CIF dictionary.
The elements of the diffractometer orientation matrix. These define the dimensions of the
reciprocal cell and its orientation to the local diffractometer axes. See _diffrn_orient_matrix_type.
diffrn_orient_matrix
Corresponds to the _diffrn_orient_matrix_ub_13 term in the IUCr Core CIF dictionary.
The elements of the diffractometer orientation matrix. These define the dimensions of the
reciprocal cell and its orientation to the local diffractometer axes. See _diffrn_orient_matrix_type.
diffrn_orient_matrix
Corresponds to the _diffrn_orient_matrix_ub_21 term in the IUCr Core CIF dictionary.
The elements of the diffractometer orientation matrix. These define the dimensions of the
reciprocal cell and its orientation to the local diffractometer axes. See _diffrn_orient_matrix_type.
diffrn_orient_matrix
Corresponds to the _diffrn_orient_matrix_ub_22 term in the IUCr Core CIF dictionary.
The elements of the diffractometer orientation matrix. These define the dimensions of the
reciprocal cell and its orientation to the local diffractometer axes. See _diffrn_orient_matrix_type.
diffrn_orient_matrix
Corresponds to the _diffrn_orient_matrix_ub_23 term in the IUCr Core CIF dictionary.
The elements of the diffractometer orientation matrix. These define the dimensions of the
reciprocal cell and its orientation to the local diffractometer axes. See _diffrn_orient_matrix_type.
diffrn_orient_matrix
Corresponds to the _diffrn_orient_matrix_ub_31 term in the IUCr Core CIF dictionary.
The elements of the diffractometer orientation matrix. These define the dimensions of the
reciprocal cell and its orientation to the local diffractometer axes. See _diffrn_orient_matrix_type.
diffrn_orient_matrix
Corresponds to the _diffrn_orient_matrix_ub_32 term in the IUCr Core CIF dictionary.
The elements of the diffractometer orientation matrix. These define the dimensions of the
reciprocal cell and its orientation to the local diffractometer axes. See _diffrn_orient_matrix_type.
diffrn_orient_matrix
Corresponds to the _diffrn_orient_matrix_ub_33 term in the IUCr Core CIF dictionary.
Diffractometer angles of a reflection used to define the orientation matrix in degrees. See
_diffrn_orient_matrix_UB_ and _diffrn_orient_refln_index_h, *_k and *_l.
diffrn_orient_refln
Corresponds to the _diffrn_orient_refln_angle_chi term in the IUCr Core CIF dictionary.
Diffractometer angles of a reflection used to define the orientation matrix in degrees. See
_diffrn_orient_matrix_UB_ and _diffrn_orient_refln_index_h, *_k and *_l.
diffrn_orient_refln
Corresponds to the _diffrn_orient_refln_angle_kappa term in the IUCr Core CIF dictionary.
Diffractometer angles of a reflection used to define the orientation matrix in degrees. See
_diffrn_orient_matrix_UB_ and _diffrn_orient_refln_index_h, *_k and *_l.
diffrn_orient_refln
Corresponds to the _diffrn_orient_refln_angle_omega term in the IUCr Core CIF dictionary.
Diffractometer angles of a reflection used to define the orientation matrix in degrees. See
_diffrn_orient_matrix_UB_ and _diffrn_orient_refln_index_h, *_k and *_l.
diffrn_orient_refln
Corresponds to the _diffrn_orient_refln_angle_phi term in the IUCr Core CIF dictionary.
Diffractometer angles of a reflection used to define the orientation matrix in degrees. See
_diffrn_orient_matrix_UB_ and _diffrn_orient_refln_index_h, *_k and *_l.
diffrn_orient_refln
Corresponds to the _diffrn_orient_refln_angle_psi term in the IUCr Core CIF dictionary.
Diffractometer angles of a reflection used to define the orientation matrix in degrees. See
_diffrn_orient_matrix_UB_ and _diffrn_orient_refln_index_h, *_k and *_l.
diffrn_orient_refln
Corresponds to the _diffrn_orient_refln_angle_theta term in the IUCr Core CIF dictionary.
The indices of a reflection used to define the orientation matrix. See _diffrn_orient_matrix_.
diffrn_orient_refln
Corresponds to the _diffrn_orient_refln_index_h term in the IUCr Core CIF dictionary.
The indices of a reflection used to define the orientation matrix. See _diffrn_orient_matrix_.
diffrn_orient_refln
Corresponds to the _diffrn_orient_refln_index_k term in the IUCr Core CIF dictionary.
The indices of a reflection used to define the orientation matrix. See _diffrn_orient_matrix_.
diffrn_orient_refln
Corresponds to the _diffrn_orient_refln_index_l term in the IUCr Core CIF dictionary.
Corresponds to the _diffrn_radiation_collimation term in the IUCr Core CIF dictionary.
The collimation or focusing applied to the radiation.
diffrn_radiation
Corresponds to the _diffrn_radiation_filter_edge term in the IUCr Core CIF dictionary.
Absorption edge in angstroms of the radiation filter used.
diffrn_radiation
Corresponds to the _diffrn_radiation_inhomogeneity term in the IUCr Core CIF dictionary.
Halfwidth in millimetres of the incident beam in the direction perpendicular to the diffraction
plane.
diffrn_radiation
Corresponds to the _diffrn_radiation_monochromator term in the IUCr Core CIF dictionary.
The method used to obtain monochromatic radiation. If a mono chromator crystal is used, the
material and the indices of the Bragg reflection are specified.
diffrn_radiation
Corresponds to the _diffrn_radiation_polarisn_norm term in the IUCr Core CIF dictionary.
The angle in degrees, as viewed from the specimen, between the perpendicular component of the
polarization and the diffraction plane. See _diffrn_radiation_polarisn_ratio.
diffrn_radiation
Corresponds to the _diffrn_radiation_polarisn_ratio term in the IUCr Core CIF dictionary.
Polarization ratio of the diffraction beam incident on the crystal. It is the ratio of the
perpendicularly polarized to the parallel polarized components of the radiation. The perpendicular
component forms an angle of _diffrn_radiation_polarisn_norm to the normal to the diffraction plane of
the sample (i.e. the plane containing the incident and reflected beams).
diffrn_radiation
Corresponds to the _diffrn_radiation_probe term in the IUCr Core CIF dictionary.
The nature of the radiation used (i.e. the name of the subatomic particle or the region of the
electromagnetic spectrum). It is strongly recommended that this information be given, so that the probe
radiation can be simply determined.
diffrn_radiation
xray
neutron
electron
gamma
Corresponds to the _diffrn_radiation_type term in the IUCr Core CIF dictionary.
The type of the radiation. This is used to give a more detailed description than
_diffrn_radiation_probe and is typically a description of the Xray wavelength in Siegbahn notation.
diffrn_radiation
Corresponds to the _diffrn_radiation_xray_symbol term in the IUCr Core CIF dictionary.
The IUPAC symbol for the Xray wavelength for the probe radiation.
diffrn_radiation
KL~3~
KL~2~
KM~3~
KL~2,3~
Corresponds to the _diffrn_radiation_wavelength term in the IUCr Core CIF dictionary.
The radiation wavelength in angstroms.
diffrn_radiation_wavelength
Corresponds to the _diffrn_radiation_wavelength_determination term in the IUCr Core CIF dictionary.
The method of determination of incident wavelength.
diffrn_radiation_wavelength
fundamental
estimated
refined
Corresponds to the _diffrn_radiation_wavelength_id term in the IUCr Core CIF dictionary.
An arbitrary code identifying each value of _diffrn_radiation_wavelength. Items in the
DIFFRN_RADIATION category are looped when multiple wavelengths are used. This code is used to link with
the _diffrn_refln_ list. It must match with one of the _diffrn_refln_wavelength_id codes.
diffrn_radiation_wavelength
Corresponds to the _diffrn_radiation_wavelength_wt term in the IUCr Core CIF dictionary.
The relative weight of a wavelength identified by the code _diffrn_radiation_wavelength_id in the
list of wavelengths.
diffrn_radiation_wavelength
The diffractometer angles of a reflection in degrees. These correspond to the specified orientation
matrix and the original measured cell before any subsequent cell transformations.
diffrn_refln
Corresponds to the _diffrn_refln_angle_chi term in the IUCr Core CIF dictionary.
The diffractometer angles of a reflection in degrees. These correspond to the specified orientation
matrix and the original measured cell before any subsequent cell transformations.
diffrn_refln
Corresponds to the _diffrn_refln_angle_kappa term in the IUCr Core CIF dictionary.
The diffractometer angles of a reflection in degrees. These correspond to the specified orientation
matrix and the original measured cell before any subsequent cell transformations.
diffrn_refln
Corresponds to the _diffrn_refln_angle_omega term in the IUCr Core CIF dictionary.
The diffractometer angles of a reflection in degrees. These correspond to the specified orientation
matrix and the original measured cell before any subsequent cell transformations.
diffrn_refln
Corresponds to the _diffrn_refln_angle_phi term in the IUCr Core CIF dictionary.
The diffractometer angles of a reflection in degrees. These correspond to the specified orientation
matrix and the original measured cell before any subsequent cell transformations.
diffrn_refln
Corresponds to the _diffrn_refln_angle_psi term in the IUCr Core CIF dictionary.
The diffractometer angles of a reflection in degrees. These correspond to the specified orientation
matrix and the original measured cell before any subsequent cell transformations.
diffrn_refln
Corresponds to the _diffrn_refln_angle_theta term in the IUCr Core CIF dictionary.
Corresponds to the _diffrn_refln_attenuator_code term in the IUCr Core CIF dictionary.
The code identifying the attenuator setting for this reflection. This code must match one of the
_diffrn_attenuator_code values.
diffrn_refln
Corresponds to the _diffrn_refln_class_code term in the IUCr Core CIF dictionary.
The code identifying the class to which this reflection has been assigned. This code must match a
value of _diffrn_reflns_class_code. Reflections may be grouped into classes for a variety of purposes.
For example, for modulated structures each reflection class may be defined by the number m=summ~i~,
where the m~i~ are the integer coefficients that, in addition to h,k,l, index the corresponding
diffraction vector in the basis defined for the reciprocal lattice.
diffrn_refln
The diffractometer counts for the measurements: background before the peak, background after the
peak, net counts after background removed, counts for peak scan or position, and the total counts
(background plus peak).
diffrn_refln
Corresponds to the _diffrn_refln_counts_bg_1 term in the IUCr Core CIF dictionary.
The diffractometer counts for the measurements: background before the peak, background after the
peak, net counts after background removed, counts for peak scan or position, and the total counts
(background plus peak).
diffrn_refln
Corresponds to the _diffrn_refln_counts_bg_2 term in the IUCr Core CIF dictionary.
The diffractometer counts for the measurements: background before the peak, background after the
peak, net counts after background removed, counts for peak scan or position, and the total counts
(background plus peak).
diffrn_refln
Corresponds to the _diffrn_refln_counts_net term in the IUCr Core CIF dictionary.
The diffractometer counts for the measurements: background before the peak, background after the
peak, net counts after background removed, counts for peak scan or position, and the total counts
(background plus peak).
diffrn_refln
Corresponds to the _diffrn_refln_counts_peak term in the IUCr Core CIF dictionary.
The diffractometer counts for the measurements: background before the peak, background after the
peak, net counts after background removed, counts for peak scan or position, and the total counts
(background plus peak).
diffrn_refln
Corresponds to the _diffrn_refln_counts_total term in the IUCr Core CIF dictionary.
Corresponds to the _diffrn_refln_crystal_id term in the IUCr Core CIF dictionary.
Code identifying each crystal if multiple crystals are used. Is used to link with _exptl_crystal_id
in the _exptl_crystal_ list.
diffrn_refln
Total slit apertures in degrees in the diffraction plane (*_horiz) and perpendicular to the
diffraction plane (*_vert).
diffrn_refln
Corresponds to the _diffrn_refln_detect_slit_horiz term in the IUCr Core CIF dictionary.
Total slit apertures in degrees in the diffraction plane (*_horiz) and perpendicular to the
diffraction plane (*_vert).
diffrn_refln
Corresponds to the _diffrn_refln_detect_slit_vert term in the IUCr Core CIF dictionary.
Corresponds to the _diffrn_refln_elapsed_time term in the IUCr Core CIF dictionary.
Elapsed time in minutes from the start of the diffraction experiment to the measurement of this
intensity.
diffrn_refln
Miller indices of a measured reflection. These need not match the _refln_index_h, *_k, *_l values
if a transformation of the original measured cell has taken place. Details of the cell transformation
are given in _diffrn_reflns_reduction_process. See also _diffrn_reflns_transf_matrix_.
diffrn_refln
Corresponds to the _diffrn_refln_index_h term in the IUCr Core CIF dictionary.
Miller indices of a measured reflection. These need not match the _refln_index_h, *_k, *_l values
if a transformation of the original measured cell has taken place. Details of the cell transformation
are given in _diffrn_reflns_reduction_process. See also _diffrn_reflns_transf_matrix_.
diffrn_refln
Corresponds to the _diffrn_refln_index_k term in the IUCr Core CIF dictionary.
Miller indices of a measured reflection. These need not match the _refln_index_h, *_k, *_l values
if a transformation of the original measured cell has taken place. Details of the cell transformation
are given in _diffrn_reflns_reduction_process. See also _diffrn_reflns_transf_matrix_.
diffrn_refln
Corresponds to the _diffrn_refln_index_l term in the IUCr Core CIF dictionary.
Corresponds to the _diffrn_refln_intensity_net term in the IUCr Core CIF dictionary.
Net intensity calculated from the diffraction counts after the attenuator and standard scales have
been applied.
diffrn_refln
Corresponds to the _diffrn_refln_intensity_sigma term in the IUCr Core CIF dictionary.
Standard uncertainty (e.s.d.) of the net intensity calculated from the diffraction counts after the
attenuator and standard scales have been applied.
diffrn_refln
Corresponds to the _diffrn_refln_intensity_u term in the IUCr Core CIF dictionary.
Standard uncertainty of the net intensity calculated from the diffraction counts after the
attenuator and standard scales have been applied.
diffrn_refln
Corresponds to the _diffrn_refln_scale_group_code term in the IUCr Core CIF dictionary.
The code identifying the scale applicable to this reflection. This code must match with a specified
_diffrn_scale_group_code value.
diffrn_refln
Corresponds to the _diffrn_refln_scan_mode term in the IUCr Core CIF dictionary.
The code identifying the mode of scanning for measurements using a diffractometer. See
_diffrn_refln_scan_width and _diffrn_refln_scan_mode_backgd.
diffrn_refln
om
ot
q
Corresponds to the _diffrn_refln_scan_mode_backgd term in the IUCr Core CIF dictionary.
The code identifying the mode of scanning a reflection to measure the background intensity.
diffrn_refln
st
mo
Corresponds to the _diffrn_refln_scan_rate term in the IUCr Core CIF dictionary.
The rate of scanning a reflection in degrees per minute to measure the intensity.
diffrn_refln
Corresponds to the _diffrn_refln_scan_time_backgd term in the IUCr Core CIF dictionary.
The time spent measuring each background in seconds.
diffrn_refln
Corresponds to the _diffrn_refln_scan_width term in the IUCr Core CIF dictionary.
The scan width in degrees of the scan mode defined by the code _diffrn_refln_scan_mode.
diffrn_refln
Corresponds to the _diffrn_refln_sint/lambda term in the IUCr Core CIF dictionary.
The (sin theta)/lambda value in reciprocal angstroms for this reflection.
diffrn_refln
Corresponds to the _diffrn_refln_standard_code term in the IUCr Core CIF dictionary.
A code indicating that this reflection was measured as a standard reflection. The value must be '.'
or match one of the _diffrn_standard_refln_code values.
diffrn_refln
Corresponds to the _diffrn_refln_wavelength term in the IUCr Core CIF dictionary.
The mean wavelength in angstroms of the radiation used to measure the intensity of this reflection.
This is an important parameter for reflections measured using energydispersive detectors or the Laue
method.
diffrn_refln
Corresponds to the _diffrn_refln_wavelength_id term in the IUCr Core CIF dictionary.
Code identifying the wavelength in the _diffrn_radiation_ list.
diffrn_refln
Corresponds to the _diffrn_reflns_av_r_equivalents term in the IUCr Core CIF dictionary.
The residual [sum avdel(I) / sum av(I)] for symmetryequivalent reflections used to calculate
the average intensity av(I). The avdel(I) term is the average absolute difference between av(I) and
the individual symmetryequivalent intensities.
diffrn_reflns
Corresponds to the _diffrn_reflns_av_sigmai/neti term in the IUCr Core CIF dictionary.
Measure [sum u(net I)/sumnet I] for all measured reflections.
diffrn_reflns
Corresponds to the _diffrn_reflns_av_uneti/neti term in the IUCr Core CIF dictionary.
Measure [sum u(net I)/sumnet I] for all measured reflections.
diffrn_reflns
Corresponds to the _diffrn_reflns_laue_measured_fraction_full term in the IUCr Core CIF dictionary.
Fraction of Laue unique reflections (symmetryindependent in the Laue group) measured out to the
resolution given in _diffrn_reflns_resolution_full or _diffrn_reflns_theta_full. The Laue group always
contains a centre of symmetry so that the reflection h,k,l is always equivalent to the reflection
h,k,l even in space groups without a centre of symmetry. This number should not be less than 0.95,
since it represents the fraction of reflections measured in the part of the diffraction pattern that is
essentially complete.
diffrn_reflns
Corresponds to the _diffrn_reflns_laue_measured_fraction_max term in the IUCr Core CIF dictionary.
Fraction of Laue unique reflections (symmetryindependent in the Laue group) measured out to the
resolution given in _diffrn_reflns_resolution_max or _diffrn_reflns_theta_max. The Laue group always
contains a centre of symmetry so that the reflection h,k,l is always equivalent to the reflection
h,k,l even in space groups without a centre of symmetry.
diffrn_reflns
The limits on the Miller indices of the intensities specified by _diffrn_refln_index_h, *_k, *_l.
diffrn_reflns
Corresponds to the _diffrn_reflns_limit_h_max term in the IUCr Core CIF dictionary.
The limits on the Miller indices of the intensities specified by _diffrn_refln_index_h, *_k, *_l.
diffrn_reflns
Corresponds to the _diffrn_reflns_limit_h_min term in the IUCr Core CIF dictionary.
The limits on the Miller indices of the intensities specified by _diffrn_refln_index_h, *_k, *_l.
diffrn_reflns
Corresponds to the _diffrn_reflns_limit_k_max term in the IUCr Core CIF dictionary.
The limits on the Miller indices of the intensities specified by _diffrn_refln_index_h, *_k, *_l.
diffrn_reflns
Corresponds to the _diffrn_reflns_limit_k_min term in the IUCr Core CIF dictionary.
The limits on the Miller indices of the intensities specified by _diffrn_refln_index_h, *_k, *_l.
diffrn_reflns
Corresponds to the _diffrn_reflns_limit_l_max term in the IUCr Core CIF dictionary.
The limits on the Miller indices of the intensities specified by _diffrn_refln_index_h, *_k, *_l.
diffrn_reflns
Corresponds to the _diffrn_reflns_limit_l_min term in the IUCr Core CIF dictionary.
Corresponds to the _diffrn_reflns_number term in the IUCr Core CIF dictionary.
The total number of measured intensities, excluding reflections that are classed as systematically
absent arising from translational symmetry in the crystal unit cell.
diffrn_reflns
Corresponds to the _diffrn_reflns_point_group_measured_fraction_full term in the IUCr Core CIF
dictionary.
Fraction of crystal pointgroup unique reflections (i.e. symmetryindependent in the crystal point
group) measured out to the resolution given in _diffrn_reflns_resolution_full or
_diffrn_reflns_theta_full. For space groups that do not contain a centre of symmetry the reflections
h,k,l and h,k,l are independent. This number should not be less than 0.95, since it represents the
fraction of reflections measured in the part of the diffraction pattern that is essentially complete.
diffrn_reflns
Corresponds to the _diffrn_reflns_point_group_measured_fraction_max term in the IUCr Core CIF
dictionary.
Fraction of crystal pointgroup unique reflections (i.e. symmetryindependent in the crystal point
group) measured out to the resolution given in _diffrn_reflns_resolution_max or
_diffrn_reflns_theta_max. For space groups that do not contain a centre of symmetry the reflections
h,k,l and h,k,l are independent.
diffrn_reflns
Corresponds to the _diffrn_reflns_reduction_process term in the IUCr Core CIF dictionary.
A description of the process used to reduce the intensities into structurefactor magnitudes.
diffrn_reflns
Corresponds to the _diffrn_reflns_resolution_full term in the IUCr Core CIF dictionary.
The resolution in reciprocal angstroms at which the measured reflection count is close to complete.
The fraction of unique reflections measured out to this angle is given by
_diffrn_measured_fraction_theta_full.
diffrn_reflns
Corresponds to the _diffrn_reflns_resolution_max term in the IUCr Core CIF dictionary.
Maximum resolution in reciprocal angstroms of the measured diffraction pattern. The fraction of
unique reflections measured out to this angle is given by _diffrn_measured_fraction_theta_max
diffrn_reflns
Corresponds to the _diffrn_reflns_theta_full term in the IUCr Core CIF dictionary.
The theta angle (in degrees) at which the measured reflection count is close to complete. The
fraction of unique reflections measured out to this angle is given by
_diffrn_measured_fraction_theta_full.
diffrn_reflns
Corresponds to the _diffrn_reflns_theta_max term in the IUCr Core CIF dictionary.
Maximum theta angle in degrees for the measured intensities. The fraction of unique reflections
measured out to this angle is given by _diffrn_measured_fraction_theta_max
diffrn_reflns
Corresponds to the _diffrn_reflns_theta_min term in the IUCr Core CIF dictionary.
Minimum theta angle in degrees for the measured intensities.
diffrn_reflns
Elements of the matrix used to transform the diffraction reflection indices _diffrn_refln_index_h,
*_k, *_l into the _refln_index_h, *_k, *_l indices. 11 12 13 (h k l) diffraction 21 22 23 = (h' k'
l') 31 32 33
diffrn_reflns
Corresponds to the _diffrn_reflns_transf_matrix_11 term in the IUCr Core CIF dictionary.
Elements of the matrix used to transform the diffraction reflection indices _diffrn_refln_index_h,
*_k, *_l into the _refln_index_h, *_k, *_l indices. 11 12 13 (h k l) diffraction 21 22 23 = (h' k'
l') 31 32 33
diffrn_reflns
Corresponds to the _diffrn_reflns_transf_matrix_12 term in the IUCr Core CIF dictionary.
Elements of the matrix used to transform the diffraction reflection indices _diffrn_refln_index_h,
*_k, *_l into the _refln_index_h, *_k, *_l indices. 11 12 13 (h k l) diffraction 21 22 23 = (h' k'
l') 31 32 33
diffrn_reflns
Corresponds to the _diffrn_reflns_transf_matrix_13 term in the IUCr Core CIF dictionary.
Elements of the matrix used to transform the diffraction reflection indices _diffrn_refln_index_h,
*_k, *_l into the _refln_index_h, *_k, *_l indices. 11 12 13 (h k l) diffraction 21 22 23 = (h' k'
l') 31 32 33
diffrn_reflns
Corresponds to the _diffrn_reflns_transf_matrix_21 term in the IUCr Core CIF dictionary.
Elements of the matrix used to transform the diffraction reflection indices _diffrn_refln_index_h,
*_k, *_l into the _refln_index_h, *_k, *_l indices. 11 12 13 (h k l) diffraction 21 22 23 = (h' k'
l') 31 32 33
diffrn_reflns
Corresponds to the _diffrn_reflns_transf_matrix_22 term in the IUCr Core CIF dictionary.
Elements of the matrix used to transform the diffraction reflection indices _diffrn_refln_index_h,
*_k, *_l into the _refln_index_h, *_k, *_l indices. 11 12 13 (h k l) diffraction 21 22 23 = (h' k'
l') 31 32 33
diffrn_reflns
Corresponds to the _diffrn_reflns_transf_matrix_23 term in the IUCr Core CIF dictionary.
Elements of the matrix used to transform the diffraction reflection indices _diffrn_refln_index_h,
*_k, *_l into the _refln_index_h, *_k, *_l indices. 11 12 13 (h k l) diffraction 21 22 23 = (h' k'
l') 31 32 33
diffrn_reflns
Corresponds to the _diffrn_reflns_transf_matrix_31 term in the IUCr Core CIF dictionary.
Elements of the matrix used to transform the diffraction reflection indices _diffrn_refln_index_h,
*_k, *_l into the _refln_index_h, *_k, *_l indices. 11 12 13 (h k l) diffraction 21 22 23 = (h' k'
l') 31 32 33
diffrn_reflns
Corresponds to the _diffrn_reflns_transf_matrix_32 term in the IUCr Core CIF dictionary.
Elements of the matrix used to transform the diffraction reflection indices _diffrn_refln_index_h,
*_k, *_l into the _refln_index_h, *_k, *_l indices. 11 12 13 (h k l) diffraction 21 22 23 = (h' k'
l') 31 32 33
diffrn_reflns
Corresponds to the _diffrn_reflns_transf_matrix_33 term in the IUCr Core CIF dictionary.
Corresponds to the _diffrn_reflns_class_av_r_eq term in the IUCr Core CIF dictionary.
For each reflection class, the residual [sum avdel(I)/sumav(I)] for symmetryequivalent
reflections used to calculate the average intensity av(I). The avdel(I) term is the average absolute
difference between av(I) and the individual intensities.
diffrn_reflns_class
Corresponds to the _diffrn_reflns_class_av_sgi/i term in the IUCr Core CIF dictionary.
Measure [sumu(net I)/sumnet I] for all measured intensities in a reflection class.
diffrn_reflns_class
Corresponds to the _diffrn_reflns_class_av_ui/i term in the IUCr Core CIF dictionary.
Measure [sumu(net I)/sumnet I] for all measured intensities in a reflection class.
diffrn_reflns_class
Corresponds to the _diffrn_reflns_class_code term in the IUCr Core CIF dictionary.
The code identifying a certain reflection class.
diffrn_reflns_class
Corresponds to the _diffrn_reflns_class_d_res_high term in the IUCr Core CIF dictionary.
The smallest value in angstroms of the interplanar spacings of the reflections in each reflection
class. This is called the highest resolution for this reflection class.
diffrn_reflns_class
Corresponds to the _diffrn_reflns_class_d_res_low term in the IUCr Core CIF dictionary.
The highest value in angstroms of the interplanar spacings of the reflections in each reflection
class. This is called the lowest resolution for this reflection class.
diffrn_reflns_class
Corresponds to the _diffrn_reflns_class_description term in the IUCr Core CIF dictionary.
Description of each reflection class.
diffrn_reflns_class
Corresponds to the _diffrn_reflns_class_number term in the IUCr Core CIF dictionary.
The total number of measured intensities for each reflection class, excluding the systematic
absences arising from centring translations.
diffrn_reflns_class
Corresponds to the _diffrn_scale_group_code term in the IUCr Core CIF dictionary.
The code identifying a specific measurement group (e.g. for multifilm or multicrystal data). The
code must match a _diffrn_refln_scale_group_code in the reflection list.
diffrn_scale_group
Corresponds to the _diffrn_scale_group_i_net term in the IUCr Core CIF dictionary.
The scale for a specific measurement group which is to be multiplied with the net intensity to
place all intensities in the _diffrn_refln_ or _refln_ list on a common scale.
diffrn_scale_group
Corresponds to the _diffrn_radiation_source term in the IUCr Core CIF dictionary.
The source of radiation.
diffrn_source
Corresponds to the _diffrn_source term in the IUCr Core CIF dictionary.
The general class of the source of radiation.
diffrn_source
Corresponds to the _diffrn_source_current term in the IUCr Core CIF dictionary.
The current in milliamperes at which the radiation source was operated.
diffrn_source
Corresponds to the _diffrn_source_details term in the IUCr Core CIF dictionary.
A description of special aspects of the source.
diffrn_source
Corresponds to the _diffrn_source_power term in the IUCr Core CIF dictionary.
The power in kilowatts at which the radiation source was operated.
diffrn_source
Corresponds to the _diffrn_source_size term in the IUCr Core CIF dictionary.
The dimensions of the source as viewed from the sample.
diffrn_source
Corresponds to the _diffrn_source_takeoff_angle term in the IUCr Core CIF dictionary.
The complement of the angle in degrees between the normal to the surface of the Xray tube target
and the primary Xray beam for beams generated by traditional Xray tubes.
diffrn_source
Corresponds to the _diffrn_source_target term in the IUCr Core CIF dictionary.
The chemical element symbol for the Xray target (usually the anode) used to generate Xrays. This
can also be used for spallation sources.
diffrn_source
H
He
Li
Be
B
C
N
O
F
Ne
Na
Mg
Al
Si
P
S
Cl
Ar
K
Ca
Sc
Ti
V
Cr
Mn
Fe
Co
Ni
Cu
Zn
Ga
Ge
As
Se
Br
Kr
Rb
Sr
Y
Zr
Nb
Mo
Tc
Ru
Rh
Pd
Ag
Cd
In
Sn
Sb
Te
I
Xe
Cs
Ba
La
Ce
Pr
Nd
Pm
Sm
Eu
Gd
Tb
Dy
Ho
Er
Tm
Yb
Lu
Hf
Ta
W
Re
Os
Ir
Pt
Au
Hg
Tl
Pb
Bi
Po
At
Rn
Fr
Ra
Ac
Th
Pa
U
Np
Pu
Am
Cm
Bk
Cf
Es
Fm
Md
No
Lr
Corresponds to the _diffrn_source_type term in the IUCr Core CIF dictionary.
The make, model or name of the source of radiation.
diffrn_source
Corresponds to the _diffrn_source_voltage term in the IUCr Core CIF dictionary.
The voltage in kilovolts at which the radiation source was operated.
diffrn_source
Corresponds to the _diffrn_standard_refln_code term in the IUCr Core CIF dictionary.
The code identifying a reflection measured as a standard reflection with the indices
_diffrn_standard_refln_index_. This is the same code as the _diffrn_refln_standard_code in the
_diffrn_refln_ list.
diffrn_standard_refln
Miller indices of standard reflections used in the diffraction measurement process.
diffrn_standard_refln
Corresponds to the _diffrn_standard_refln_index_h term in the IUCr Core CIF dictionary.
Miller indices of standard reflections used in the diffraction measurement process.
diffrn_standard_refln
Corresponds to the _diffrn_standard_refln_index_k term in the IUCr Core CIF dictionary.
Miller indices of standard reflections used in the diffraction measurement process.
diffrn_standard_refln
Corresponds to the _diffrn_standard_refln_index_l term in the IUCr Core CIF dictionary.
Corresponds to the _diffrn_standards_decay_% term in the IUCr Core CIF dictionary.
The percentage decrease in the mean intensity of the set of standard reflections measured at the
start of the measurement process and at the finish. This value usually affords a measure of the overall
decay in crystal quality during the diffraction measurement process. Negative values are used in
exceptional instances where the final intensities are greater than the initial ones. If no measurable
decay has occurred, the standard uncertainty should be quoted to indicate the maximum possible value the
decay might have. A range of 3 standard uncertainties is considered possible. Thus 0.0(1) would indicate
a decay of less than 0.3% or an enhancement of less than 0.3%.
diffrn_standards
The number of reflection intensities, or the time in minutes, between the measurement of standard
reflection intensities.
diffrn_standards
Corresponds to the _diffrn_standards_interval_count term in the IUCr Core CIF dictionary.
The number of reflection intensities, or the time in minutes, between the measurement of standard
reflection intensities.
diffrn_standards
Corresponds to the _diffrn_standards_interval_time term in the IUCr Core CIF dictionary.
Corresponds to the _diffrn_standards_number term in the IUCr Core CIF dictionary.
The number of unique standard reflections used during the measurement of the diffraction
intensities.
diffrn_standards
Corresponds to the _diffrn_standards_scale_sigma term in the IUCr Core CIF dictionary.
The standard uncertainty (e.s.d.) of the individual mean standard scales applied to the intensity
data.
diffrn_standards
Corresponds to the _diffrn_standards_scale_u term in the IUCr Core CIF dictionary.
The standard uncertainty of the individual mean standard scales applied to the intensity data.
diffrn_standards
Corresponds to the _exptl_absorpt_coefficient_mu term in the IUCr Core CIF dictionary.
The absorption coefficient mu in reciprocal millimetres calculated from the atomic content of the
cell, the density and the radiation wavelength.
exptl
The maximum and minimum transmission factors applied to the diffraction pattern measured in this
experiment. These factors are also referred to as the absorption correction A or 1/A*. As this value is
the one that is applied to the measured intensities, it includes the correction for absorption by the
specimen mount and diffractometer as well as by the specimen itself.
exptl
Corresponds to the _exptl_absorpt_correction_t_max term in the IUCr Core CIF dictionary.
The maximum and minimum transmission factors applied to the diffraction pattern measured in this
experiment. These factors are also referred to as the absorption correction A or 1/A*. As this value is
the one that is applied to the measured intensities, it includes the correction for absorption by the
specimen mount and diffractometer as well as by the specimen itself.
exptl
Corresponds to the _exptl_absorpt_correction_t_min term in the IUCr Core CIF dictionary.
Corresponds to the _exptl_absorpt_correction_type term in the IUCr Core CIF dictionary.
The absorptioncorrection type and method. The value 'empirical' should NOT be used unless more
detailed information is not available.
exptl
analytical
cylinder
empirical
gaussian
integration
multiscan
none
numerical
psiscan
refdelf
sphere
Corresponds to the _exptl_absorpt_process_details term in the IUCr Core CIF dictionary.
Description of the absorption process applied to the intensities. A literature reference should be
supplied for psiscan techniques.
exptl
Corresponds to the _exptl_crystals_number term in the IUCr Core CIF dictionary.
The total number of crystals used for the measurement of intensities.
exptl
Corresponds to the _exptl_special_details term in the IUCr Core CIF dictionary.
Any special information about the experimental work prior to the intensity measurements. See also
_exptl_crystal_preparation.
exptl
Corresponds to the _exptl_transmission_factor_max term in the IUCr Core CIF dictionary.
The calculated maximum value of the transmission factor for the specimen. Its value does not
include the effects of absorption in the specimen mount. The presence of this item does not imply that
the structure factors have been corrected for absorption. The applied correction should be given by
_exptl_absorpt_correction_T_max.
exptl
Corresponds to the _exptl_transmission_factor_min term in the IUCr Core CIF dictionary.
The calculated minimum value of the transmission factor for the specimen. Its value does not
include the effects of absorption in the specimen mount. The presence of this item does not imply that
the structure factors have been corrected for absorption. The applied correction should be given by
_exptl_absorpt_correction_T_min.
exptl
Corresponds to the _exptl_crystal_colour term in the IUCr Core CIF dictionary.
The colour of the crystal.
exptl_crystal
Corresponds to the _exptl_crystal_colour_lustre term in the IUCr Core CIF dictionary.
The enumeration list of standardized names developed for the International Centre for Diffraction
Data. The colour of a crystal is given by the combination of _exptl_crystal_colour_modifier with
_exptl_crystal_colour_primary, as in 'darkgreen' or 'bluishviolet', if necessary combined with
_exptl_crystal_colour_lustre, as in 'metallicgreen'.
exptl_crystal
metallic
dull
clear
Corresponds to the _exptl_crystal_colour_modifier term in the IUCr Core CIF dictionary.
The enumeration list of standardized names developed for the International Centre for Diffraction
Data. The colour of a crystal is given by the combination of _exptl_crystal_colour_modifier with
_exptl_crystal_colour_primary, as in 'darkgreen' or 'bluishviolet', if necessary combined with
_exptl_crystal_colour_lustre, as in 'metallicgreen'.
exptl_crystal
light
dark
whitish
blackish
grayish
brownish
reddish
pinkish
orangish
yellowish
greenish
bluish
Corresponds to the _exptl_crystal_colour_primary term in the IUCr Core CIF dictionary.
The enumeration list of standardized names developed for the International Centre for Diffraction
Data. The colour of a crystal is given by the combination of _exptl_crystal_colour_modifier with
_exptl_crystal_colour_primary, as in 'darkgreen' or 'bluishviolet', if necessary combined with
_exptl_crystal_colour_lustre, as in 'metallicgreen'.
exptl_crystal
colourless
white
black
gray
brown
red
pink
orange
yellow
green
blue
violet
Corresponds to the _exptl_crystal_density_diffrn term in the IUCr Core CIF dictionary.
Density values calculated from the crystal cell and contents. The units are megagrams per cubic
metre (grams per cubic centimetre).
exptl_crystal
Corresponds to the _exptl_crystal_density_meas term in the IUCr Core CIF dictionary.
Density values measured using standard chemical and physical methods. The units are megagrams per
cubic metre (grams per cubic centimetre).
exptl_crystal
Corresponds to the _exptl_crystal_density_meas_gt term in the IUCr Core CIF dictionary.
The value above which the density measured using standard chemical and physical methods lies. The
units are megagrams per cubic metre (grams per cubic centimetre). _exptl_crystal_density_meas_gt and
_exptl_crystal_density_meas_lt should not be used to report new experimental work, for which
_exptl_crystal_density_meas should be used. These items are intended for use in reporting information in
existing databases and archives which would be misleading if reported under _exptl_crystal_density_meas.
exptl_crystal
Corresponds to the _exptl_crystal_density_meas_lt term in the IUCr Core CIF dictionary.
The value below which the density measured using standard chemical and physical methods lies. The
units are megagrams per cubic metre (grams per cubic centimetre). _exptl_crystal_density_meas_gt and
_exptl_crystal_density_meas_lt should not be used to report new experimental work, for which
_exptl_crystal_density_meas should be used. These items are intended for use in reporting information in
existing databases and archives which would be misleading if reported under _exptl_crystal_density_meas.
exptl_crystal
Corresponds to the _exptl_crystal_density_meas_temp term in the IUCr Core CIF dictionary.
Temperature in kelvins at which _exptl_crystal_density_meas was determined.
exptl_crystal
Corresponds to the _exptl_crystal_density_meas_temp_gt term in the IUCr Core CIF dictionary.
Temperature in kelvins above which _exptl_crystal_density_meas was determined.
_exptl_crystal_density_meas_temp_gt and _exptl_crystal_density_meas_temp_lt should not be used for
reporting new work, for which the correct temperature of measurement should be given. These items are
intended for use in reporting information stored in databases or archives which would be misleading if
reported under _exptl_crystal_density_meas_temp.
exptl_crystal
Corresponds to the _exptl_crystal_density_meas_temp_lt term in the IUCr Core CIF dictionary.
Temperature in kelvins below which _exptl_crystal_density_meas was determined.
_exptl_crystal_density_meas_temp_gt and _exptl_crystal_density_meas_temp_lt should not be used for
reporting new work, for which the correct temperature of measurement should be given. These items are
intended for use in reporting information stored in databases or archives which would be misleading if
reported under _exptl_crystal_density_meas_temp.
exptl_crystal
Corresponds to the _exptl_crystal_density_method term in the IUCr Core CIF dictionary.
The method used to measure _exptl_crystal_density_meas.
exptl_crystal
Corresponds to the _exptl_crystal_description term in the IUCr Core CIF dictionary.
A description of the quality and habit of the crystal. The crystal dimensions should not normally
be reported here; use instead _exptl_crystal_size_ for the gross dimensions of the crystal and
_exptl_crystal_face_ to describe the relationship between individual faces.
exptl_crystal
Corresponds to the _exptl_crystal_f_000 term in the IUCr Core CIF dictionary.
The effective number of electrons in the crystal unit cell contributing to F(000). This may contain
dispersion contributions and is calculated as F(000) = [ (sum f~r~)^2^ + (sum f~i~)^2^ ]^1/2^ f~r~ =
real part of the scattering factors at theta = 0 f~i~ = imaginary part of the scattering factors at
theta = 0 the sum is taken over each atom in the unit cell
exptl_crystal
Corresponds to the _exptl_crystal_id term in the IUCr Core CIF dictionary.
Code identifying each crystal if multiple crystals are used. It is used to link with
_diffrn_refln_crystal_id in the intensity measurements and with _refln_crystal_id in the _refln_ list.
exptl_crystal
Corresponds to the _exptl_crystal_preparation term in the IUCr Core CIF dictionary.
Details of crystal growth and preparation of the crystal (e.g. mounting) prior to the intensity
measurements.
exptl_crystal
Corresponds to the _exptl_crystal_pressure_history term in the IUCr Core CIF dictionary.
Relevant details concerning the pressure history of the sample.
exptl_crystal
Corresponds to the _exptl_crystal_recrystallization_method term in the IUCr Core CIF dictionary.
Describes the method used to recrystallize the sample. Sufficient details should be given for the
procedure to be repeated. The temperature or temperatures should be given as well as details of the
solvent, flux or carrier gas with concentrations or pressures and ambient atmosphere.
exptl_crystal
The maximum, medial and minimum dimensions in millimetres of the crystal. If the crystal is a
sphere, then the *_rad item is its radius. If the crystal is a cylinder, then the *_rad item is its
radius and the *_length item is its length. These may appear in a list with _exptl_crystal_id if
multiple crystals are used in the experiment.
exptl_crystal
Corresponds to the _exptl_crystal_size_length term in the IUCr Core CIF dictionary.
The maximum, medial and minimum dimensions in millimetres of the crystal. If the crystal is a
sphere, then the *_rad item is its radius. If the crystal is a cylinder, then the *_rad item is its
radius and the *_length item is its length. These may appear in a list with _exptl_crystal_id if
multiple crystals are used in the experiment.
exptl_crystal
Corresponds to the _exptl_crystal_size_max term in the IUCr Core CIF dictionary.
The maximum, medial and minimum dimensions in millimetres of the crystal. If the crystal is a
sphere, then the *_rad item is its radius. If the crystal is a cylinder, then the *_rad item is its
radius and the *_length item is its length. These may appear in a list with _exptl_crystal_id if
multiple crystals are used in the experiment.
exptl_crystal
Corresponds to the _exptl_crystal_size_mid term in the IUCr Core CIF dictionary.
The maximum, medial and minimum dimensions in millimetres of the crystal. If the crystal is a
sphere, then the *_rad item is its radius. If the crystal is a cylinder, then the *_rad item is its
radius and the *_length item is its length. These may appear in a list with _exptl_crystal_id if
multiple crystals are used in the experiment.
exptl_crystal
Corresponds to the _exptl_crystal_size_min term in the IUCr Core CIF dictionary.
The maximum, medial and minimum dimensions in millimetres of the crystal. If the crystal is a
sphere, then the *_rad item is its radius. If the crystal is a cylinder, then the *_rad item is its
radius and the *_length item is its length. These may appear in a list with _exptl_crystal_id if
multiple crystals are used in the experiment.
exptl_crystal
Corresponds to the _exptl_crystal_size_rad term in the IUCr Core CIF dictionary.
Corresponds to the _exptl_crystal_thermal_history term in the IUCr Core CIF dictionary.
Relevant details concerning the thermal history of the sample.
exptl_crystal
The goniometer angle settings in degrees when the perpendicular to the specified crystal face is
aligned along a specified direction (e.g. the bisector of the incident and reflected beams in an optical
goniometer).
exptl_crystal_face
Corresponds to the _exptl_crystal_face_diffr_chi term in the IUCr Core CIF dictionary.
The goniometer angle settings in degrees when the perpendicular to the specified crystal face is
aligned along a specified direction (e.g. the bisector of the incident and reflected beams in an optical
goniometer).
exptl_crystal_face
Corresponds to the _exptl_crystal_face_diffr_kappa term in the IUCr Core CIF dictionary.
The goniometer angle settings in degrees when the perpendicular to the specified crystal face is
aligned along a specified direction (e.g. the bisector of the incident and reflected beams in an optical
goniometer).
exptl_crystal_face
Corresponds to the _exptl_crystal_face_diffr_phi term in the IUCr Core CIF dictionary.
The goniometer angle settings in degrees when the perpendicular to the specified crystal face is
aligned along a specified direction (e.g. the bisector of the incident and reflected beams in an optical
goniometer).
exptl_crystal_face
Corresponds to the _exptl_crystal_face_diffr_psi term in the IUCr Core CIF dictionary.
Miller indices of the crystal face associated with the value _exptl_crystal_face_perp_dist.
exptl_crystal_face
Corresponds to the _exptl_crystal_face_index_h term in the IUCr Core CIF dictionary.
Miller indices of the crystal face associated with the value _exptl_crystal_face_perp_dist.
exptl_crystal_face
Corresponds to the _exptl_crystal_face_index_k term in the IUCr Core CIF dictionary.
Miller indices of the crystal face associated with the value _exptl_crystal_face_perp_dist.
exptl_crystal_face
Corresponds to the _exptl_crystal_face_index_l term in the IUCr Core CIF dictionary.
Corresponds to the _exptl_crystal_face_perp_dist term in the IUCr Core CIF dictionary.
The perpendicular distance in millimetres from the face to the centre of rotation of the crystal.
exptl_crystal_face
Corresponds to the _geom_special_details term in the IUCr Core CIF dictionary.
The description of geometrical information not covered by the existing data names in the geometry
categories, such as leastsquares planes.
geom
Corresponds to the _geom_angle term in the IUCr Core CIF dictionary.
Angle in degrees defined by the three sites _geom_angle_atom_site_label_1, *_2 and *_3. The site at
*_2 is at the apex of the angle.
geom_angle
The labels of the three atom sites which define the angle given by _geom_angle. These must match
labels specified as _atom_site_label in the atom list. Label 2 identifies the site at the apex of the
angle.
geom_angle
Corresponds to the _geom_angle_atom_site_label_1 term in the IUCr Core CIF dictionary.
The labels of the three atom sites which define the angle given by _geom_angle. These must match
labels specified as _atom_site_label in the atom list. Label 2 identifies the site at the apex of the
angle.
geom_angle
Corresponds to the _geom_angle_atom_site_label_2 term in the IUCr Core CIF dictionary.
The labels of the three atom sites which define the angle given by _geom_angle. These must match
labels specified as _atom_site_label in the atom list. Label 2 identifies the site at the apex of the
angle.
geom_angle
Corresponds to the _geom_angle_atom_site_label_3 term in the IUCr Core CIF dictionary.
Corresponds to the _geom_angle_publ_flag term in the IUCr Core CIF dictionary.
This code signals whether the angle is referred to in a publication or should be placed in a table
of significant angles.
geom_angle
no
n
yes
y
The symmetry code of each atom site as the symmetryequivalent position number 'n' and the cell
translation number 'klm'. These numbers are combined to form the code 'n klm' or n_klm. The character
string n_klm is composed as follows: n refers to the symmetry operation that is applied to the
coordinates stored in _atom_site_fract_x, _atom_site_fract_y and _atom_site_fract_z. It must match a
number given in _space_group_symop_id. k, l and m refer to the translations that are subsequently
applied to the symmetrytransformed coordinates to generate the atom used in calculating the angle.
These translations (x,y,z) are related to (k,l,m) by the relations k = 5 + x l = 5 + y m = 5 + z By
adding 5 to the translations, the use of negative numbers is avoided.
geom_angle
Corresponds to the _geom_angle_site_symmetry_1 term in the IUCr Core CIF dictionary.
The symmetry code of each atom site as the symmetryequivalent position number 'n' and the cell
translation number 'klm'. These numbers are combined to form the code 'n klm' or n_klm. The character
string n_klm is composed as follows: n refers to the symmetry operation that is applied to the
coordinates stored in _atom_site_fract_x, _atom_site_fract_y and _atom_site_fract_z. It must match a
number given in _space_group_symop_id. k, l and m refer to the translations that are subsequently
applied to the symmetrytransformed coordinates to generate the atom used in calculating the angle.
These translations (x,y,z) are related to (k,l,m) by the relations k = 5 + x l = 5 + y m = 5 + z By
adding 5 to the translations, the use of negative numbers is avoided.
geom_angle
Corresponds to the _geom_angle_site_symmetry_2 term in the IUCr Core CIF dictionary.
The symmetry code of each atom site as the symmetryequivalent position number 'n' and the cell
translation number 'klm'. These numbers are combined to form the code 'n klm' or n_klm. The character
string n_klm is composed as follows: n refers to the symmetry operation that is applied to the
coordinates stored in _atom_site_fract_x, _atom_site_fract_y and _atom_site_fract_z. It must match a
number given in _space_group_symop_id. k, l and m refer to the translations that are subsequently
applied to the symmetrytransformed coordinates to generate the atom used in calculating the angle.
These translations (x,y,z) are related to (k,l,m) by the relations k = 5 + x l = 5 + y m = 5 + z By
adding 5 to the translations, the use of negative numbers is avoided.
geom_angle
Corresponds to the _geom_angle_site_symmetry_3 term in the IUCr Core CIF dictionary.
The labels of two atom sites that form a bond. These must match labels specified as
_atom_site_label in the atom list.
geom_bond
Corresponds to the _geom_bond_atom_site_label_1 term in the IUCr Core CIF dictionary.
The labels of two atom sites that form a bond. These must match labels specified as
_atom_site_label in the atom list.
geom_bond
Corresponds to the _geom_bond_atom_site_label_2 term in the IUCr Core CIF dictionary.
Corresponds to the _geom_bond_distance term in the IUCr Core CIF dictionary.
The intramolecular bond distance in angstroms.
geom_bond
Corresponds to the _geom_bond_multiplicity term in the IUCr Core CIF dictionary.
The number of times the given bond appears in the environment of the atoms labelled
_geom_bond_atom_site_label_1. In cases where the full list of bonds is given, one of the series of
equivalent bonds may be assigned the appropriate multiplicity while the others are assigned a value of
0.
geom_bond
Corresponds to the _geom_bond_publ_flag term in the IUCr Core CIF dictionary.
This code signals whether the bond distance is referred to in a publication or should be placed in
a list of significant bond distances.
geom_bond
no
n
yes
y
The symmetry code of each atom site as the symmetryequivalent position number 'n' and the cell
translation number 'klm'. These numbers are combined to form the code 'n klm' or n_klm. The character
string n_klm is composed as follows: n refers to the symmetry operation that is applied to the
coordinates stored in _atom_site_fract_x, _atom_site_fract_y and _atom_site_fract_z. It must match a
number given in _space_group_symop_id. k, l and m refer to the translations that are subsequently
applied to the symmetrytransformed coordinates to generate the atom used in calculating the bond. These
translations (x,y,z) are related to (k,l,m) by the relations k = 5 + x l = 5 + y m = 5 + z By adding 5
to the translations, the use of negative numbers is avoided.
geom_bond
Corresponds to the _geom_bond_site_symmetry_1 term in the IUCr Core CIF dictionary.
The symmetry code of each atom site as the symmetryequivalent position number 'n' and the cell
translation number 'klm'. These numbers are combined to form the code 'n klm' or n_klm. The character
string n_klm is composed as follows: n refers to the symmetry operation that is applied to the
coordinates stored in _atom_site_fract_x, _atom_site_fract_y and _atom_site_fract_z. It must match a
number given in _space_group_symop_id. k, l and m refer to the translations that are subsequently
applied to the symmetrytransformed coordinates to generate the atom used in calculating the bond. These
translations (x,y,z) are related to (k,l,m) by the relations k = 5 + x l = 5 + y m = 5 + z By adding 5
to the translations, the use of negative numbers is avoided.
geom_bond
Corresponds to the _geom_bond_site_symmetry_2 term in the IUCr Core CIF dictionary.
Corresponds to the _geom_bond_valence term in the IUCr Core CIF dictionary.
The bond valence calculated from _geom_bond_distance.
geom_bond
The labels of two atom sites that are within contact distance. The labels must match
_atom_site_label codes in the atom list.
geom_contact
Corresponds to the _geom_contact_atom_site_label_1 term in the IUCr Core CIF dictionary.
The labels of two atom sites that are within contact distance. The labels must match
_atom_site_label codes in the atom list.
geom_contact
Corresponds to the _geom_contact_atom_site_label_2 term in the IUCr Core CIF dictionary.
Corresponds to the _geom_contact_distance term in the IUCr Core CIF dictionary.
The interatomic contact distance in angstroms.
geom_contact
Corresponds to the _geom_contact_publ_flag term in the IUCr Core CIF dictionary.
This code signals whether the contact distance is referred to in a publication or should be placed
in a list of significant contact distances.
geom_contact
no
n
yes
y
The symmetry code of each atom site as the symmetryequivalent position number 'n' and the cell
translation number 'klm'. These numbers are combined to form the code 'n klm' or n_klm. The character
string n_klm is composed as follows: n refers to the symmetry operation that is applied to the
coordinates stored in _atom_site_fract_x, _atom_site_fract_y and _atom_site_fract_z. It must match a
number given in _space_group_symop_id. k, l and m refer to the translations that are subsequently
applied to the symmetrytransformed coordinates to generate the atom used in calculating the contact.
These translations (x,y,z) are related to (k,l,m) by the relations k = 5 + x l = 5 + y m = 5 + z By
adding 5 to the translations, the use of negative numbers is avoided.
geom_contact
Corresponds to the _geom_contact_site_symmetry_1 term in the IUCr Core CIF dictionary.
The symmetry code of each atom site as the symmetryequivalent position number 'n' and the cell
translation number 'klm'. These numbers are combined to form the code 'n klm' or n_klm. The character
string n_klm is composed as follows: n refers to the symmetry operation that is applied to the
coordinates stored in _atom_site_fract_x, _atom_site_fract_y and _atom_site_fract_z. It must match a
number given in _space_group_symop_id. k, l and m refer to the translations that are subsequently
applied to the symmetrytransformed coordinates to generate the atom used in calculating the contact.
These translations (x,y,z) are related to (k,l,m) by the relations k = 5 + x l = 5 + y m = 5 + z By
adding 5 to the translations, the use of negative numbers is avoided.
geom_contact
Corresponds to the _geom_contact_site_symmetry_2 term in the IUCr Core CIF dictionary.
Corresponds to the _geom_hbond_angle_dha term in the IUCr Core CIF dictionary.
Angle in degrees defined by the three sites _geom_hbond_atom_site_label_D, *_H and *_A. The site at
*_H (the hydrogen atom participating in the interaction) is at the apex of the angle.
geom_hbond
The labels of three atom sites (respectively, the donor atom, hydrogen atom and acceptor atom)
participating in a hydrogen bond. These must match labels specified as _atom_site_label in the atom
list.
geom_hbond
Corresponds to the _geom_hbond_atom_site_label_d term in the IUCr Core CIF dictionary.
The labels of three atom sites (respectively, the donor atom, hydrogen atom and acceptor atom)
participating in a hydrogen bond. These must match labels specified as _atom_site_label in the atom
list.
geom_hbond
Corresponds to the _geom_hbond_atom_site_label_h term in the IUCr Core CIF dictionary.
The labels of three atom sites (respectively, the donor atom, hydrogen atom and acceptor atom)
participating in a hydrogen bond. These must match labels specified as _atom_site_label in the atom
list.
geom_hbond
Corresponds to the _geom_hbond_atom_site_label_a term in the IUCr Core CIF dictionary.
Distances in angstroms between the donor and hydrogen (*_DH), hydrogen and acceptor (*_HA) and
donor and acceptor (*_DA) sites in a hydrogen bond.
geom_hbond
Corresponds to the _geom_hbond_distance_dh term in the IUCr Core CIF dictionary.
Distances in angstroms between the donor and hydrogen (*_DH), hydrogen and acceptor (*_HA) and
donor and acceptor (*_DA) sites in a hydrogen bond.
geom_hbond
Corresponds to the _geom_hbond_distance_ha term in the IUCr Core CIF dictionary.
Distances in angstroms between the donor and hydrogen (*_DH), hydrogen and acceptor (*_HA) and
donor and acceptor (*_DA) sites in a hydrogen bond.
geom_hbond
Corresponds to the _geom_hbond_distance_da term in the IUCr Core CIF dictionary.
Corresponds to the _geom_hbond_publ_flag term in the IUCr Core CIF dictionary.
This code signals whether the hydrogenbond information is referred to in a publication or should
be placed in a table of significant hydrogenbond geometry.
geom_hbond
no
n
yes
y
The symmetry code of each atom site as the symmetryequivalent position number 'n' and the cell
translation number 'klm'. These numbers are combined to form the code 'n klm' or n_klm. The character
string n_klm is composed as follows: n refers to the symmetry operation that is applied to the
coordinates stored in _atom_site_fract_x, _atom_site_fract_y and _atom_site_fract_z. It must match a
number given in _space_group_symop_id. k, l and m refer to the translations that are subsequently
applied to the symmetrytransformed coordinates to generate the atom used in calculating the hydrogen
bond. These translations (x,y,z) are related to (k,l,m) by the relations k = 5 + x l = 5 + y m = 5 + z
By adding 5 to the translations, the use of negative numbers is avoided.
geom_hbond
Corresponds to the _geom_hbond_site_symmetry_d term in the IUCr Core CIF dictionary.
The symmetry code of each atom site as the symmetryequivalent position number 'n' and the cell
translation number 'klm'. These numbers are combined to form the code 'n klm' or n_klm. The character
string n_klm is composed as follows: n refers to the symmetry operation that is applied to the
coordinates stored in _atom_site_fract_x, _atom_site_fract_y and _atom_site_fract_z. It must match a
number given in _space_group_symop_id. k, l and m refer to the translations that are subsequently
applied to the symmetrytransformed coordinates to generate the atom used in calculating the hydrogen
bond. These translations (x,y,z) are related to (k,l,m) by the relations k = 5 + x l = 5 + y m = 5 + z
By adding 5 to the translations, the use of negative numbers is avoided.
geom_hbond
Corresponds to the _geom_hbond_site_symmetry_h term in the IUCr Core CIF dictionary.
The symmetry code of each atom site as the symmetryequivalent position number 'n' and the cell
translation number 'klm'. These numbers are combined to form the code 'n klm' or n_klm. The character
string n_klm is composed as follows: n refers to the symmetry operation that is applied to the
coordinates stored in _atom_site_fract_x, _atom_site_fract_y and _atom_site_fract_z. It must match a
number given in _space_group_symop_id. k, l and m refer to the translations that are subsequently
applied to the symmetrytransformed coordinates to generate the atom used in calculating the hydrogen
bond. These translations (x,y,z) are related to (k,l,m) by the relations k = 5 + x l = 5 + y m = 5 + z
By adding 5 to the translations, the use of negative numbers is avoided.
geom_hbond
Corresponds to the _geom_hbond_site_symmetry_a term in the IUCr Core CIF dictionary.
Corresponds to the _geom_torsion term in the IUCr Core CIF dictionary.
The torsion angle in degrees bounded by the four atom sites identified by the
_geom_torsion_atom_site_label_ codes. These must match labels specified as _atom_site_label in the atom
list. The torsionangle definition should be that of Klyne and Prelog. Ref: Klyne, W. & Prelog, V.
(1960). Experientia, 16, 521523.
geom_torsion
The labels of the four atom sites which define the torsion angle specified by _geom_torsion. These
must match codes specified as _atom_site_label in the atom list. The torsionangle definition should be
that of Klyne and Prelog. The vector direction *_label_2 to *_label_3 is the viewing direction, and the
torsion angle is the angle of twist required to superimpose the projection of the vector between site 2
and site 1 onto the projection of the vector between site 3 and site 4. Clockwise torsions are positive,
anticlockwise torsions are negative. Ref: Klyne, W. & Prelog, V. (1960). Experientia, 16, 521523.
geom_torsion
Corresponds to the _geom_torsion_atom_site_label_1 term in the IUCr Core CIF dictionary.
The labels of the four atom sites which define the torsion angle specified by _geom_torsion. These
must match codes specified as _atom_site_label in the atom list. The torsionangle definition should be
that of Klyne and Prelog. The vector direction *_label_2 to *_label_3 is the viewing direction, and the
torsion angle is the angle of twist required to superimpose the projection of the vector between site 2
and site 1 onto the projection of the vector between site 3 and site 4. Clockwise torsions are positive,
anticlockwise torsions are negative. Ref: Klyne, W. & Prelog, V. (1960). Experientia, 16, 521523.
geom_torsion
Corresponds to the _geom_torsion_atom_site_label_2 term in the IUCr Core CIF dictionary.
The labels of the four atom sites which define the torsion angle specified by _geom_torsion. These
must match codes specified as _atom_site_label in the atom list. The torsionangle definition should be
that of Klyne and Prelog. The vector direction *_label_2 to *_label_3 is the viewing direction, and the
torsion angle is the angle of twist required to superimpose the projection of the vector between site 2
and site 1 onto the projection of the vector between site 3 and site 4. Clockwise torsions are positive,
anticlockwise torsions are negative. Ref: Klyne, W. & Prelog, V. (1960). Experientia, 16, 521523.
geom_torsion
Corresponds to the _geom_torsion_atom_site_label_3 term in the IUCr Core CIF dictionary.
The labels of the four atom sites which define the torsion angle specified by _geom_torsion. These
must match codes specified as _atom_site_label in the atom list. The torsionangle definition should be
that of Klyne and Prelog. The vector direction *_label_2 to *_label_3 is the viewing direction, and the
torsion angle is the angle of twist required to superimpose the projection of the vector between site 2
and site 1 onto the projection of the vector between site 3 and site 4. Clockwise torsions are positive,
anticlockwise torsions are negative. Ref: Klyne, W. & Prelog, V. (1960). Experientia, 16, 521523.
geom_torsion
Corresponds to the _geom_torsion_atom_site_label_4 term in the IUCr Core CIF dictionary.
Corresponds to the _geom_torsion_publ_flag term in the IUCr Core CIF dictionary.
This code signals whether the torsion angle is referred to in a publication or should be placed in
a table of significant torsion angles.
geom_torsion
no
n
yes
y
The symmetry code of each atom site as the symmetryequivalent position number 'n' and the cell
translation number 'klm'. These numbers are combined to form the code 'n klm' or n_klm. The character
string n_klm is composed as follows: n refers to the symmetry operation that is applied to the
coordinates stored in _atom_site_fract_x, _atom_site_fract_y and _atom_site_fract_z. It must match a
number given in _space_group_symop_id. k, l and m refer to the translations that are subsequently
applied to the symmetrytransformed coordinates to generate the atom used in calculating the angle.
These translations (x,y,z) are related to (k,l,m) by the relations k = 5 + x l = 5 + y m = 5 + z By
adding 5 to the translations, the use of negative numbers is avoided.
geom_torsion
Corresponds to the _geom_torsion_site_symmetry_1 term in the IUCr Core CIF dictionary.
The symmetry code of each atom site as the symmetryequivalent position number 'n' and the cell
translation number 'klm'. These numbers are combined to form the code 'n klm' or n_klm. The character
string n_klm is composed as follows: n refers to the symmetry operation that is applied to the
coordinates stored in _atom_site_fract_x, _atom_site_fract_y and _atom_site_fract_z. It must match a
number given in _space_group_symop_id. k, l and m refer to the translations that are subsequently
applied to the symmetrytransformed coordinates to generate the atom used in calculating the angle.
These translations (x,y,z) are related to (k,l,m) by the relations k = 5 + x l = 5 + y m = 5 + z By
adding 5 to the translations, the use of negative numbers is avoided.
geom_torsion
Corresponds to the _geom_torsion_site_symmetry_2 term in the IUCr Core CIF dictionary.
The symmetry code of each atom site as the symmetryequivalent position number 'n' and the cell
translation number 'klm'. These numbers are combined to form the code 'n klm' or n_klm. The character
string n_klm is composed as follows: n refers to the symmetry operation that is applied to the
coordinates stored in _atom_site_fract_x, _atom_site_fract_y and _atom_site_fract_z. It must match a
number given in _space_group_symop_id. k, l and m refer to the translations that are subsequently
applied to the symmetrytransformed coordinates to generate the atom used in calculating the angle.
These translations (x,y,z) are related to (k,l,m) by the relations k = 5 + x l = 5 + y m = 5 + z By
adding 5 to the translations, the use of negative numbers is avoided.
geom_torsion
Corresponds to the _geom_torsion_site_symmetry_3 term in the IUCr Core CIF dictionary.
The symmetry code of each atom site as the symmetryequivalent position number 'n' and the cell
translation number 'klm'. These numbers are combined to form the code 'n klm' or n_klm. The character
string n_klm is composed as follows: n refers to the symmetry operation that is applied to the
coordinates stored in _atom_site_fract_x, _atom_site_fract_y and _atom_site_fract_z. It must match a
number given in _space_group_symop_id. k, l and m refer to the translations that are subsequently
applied to the symmetrytransformed coordinates to generate the atom used in calculating the angle.
These translations (x,y,z) are related to (k,l,m) by the relations k = 5 + x l = 5 + y m = 5 + z By
adding 5 to the translations, the use of negative numbers is avoided.
geom_torsion
Corresponds to the _geom_torsion_site_symmetry_4 term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_coden_astm term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_coden_cambridge term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_coeditor_address term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_coeditor_code term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_coeditor_email term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_coeditor_fax term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_coeditor_name term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_coeditor_notes term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_coeditor_phone term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_data_validation_number term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_date_accepted term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_date_from_coeditor term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_date_to_coeditor term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_date_printers_final term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_date_printers_first term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_date_proofs_in term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_date_proofs_out term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_date_recd_copyright term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_date_recd_electronic term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_date_recd_hard_copy term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_issue term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_language term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_name_full term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_page_first term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_page_last term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_paper_category term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_suppl_publ_number term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_suppl_publ_pages term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_techeditor_address term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_techeditor_code term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_techeditor_email term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_techeditor_fax term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_techeditor_name term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_techeditor_notes term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_techeditor_phone term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_volume term in the IUCr Core CIF dictionary.
Data items specified by the journal staff.
journal
Corresponds to the _journal_year term in the IUCr Core CIF dictionary.
Indexing terms supplied by the journal staff.
journal_index
Corresponds to the _journal_index_subterm term in the IUCr Core CIF dictionary.
Indexing terms supplied by the journal staff.
journal_index
Corresponds to the _journal_index_term term in the IUCr Core CIF dictionary.
Indexing terms supplied by the journal staff.
journal_index
Corresponds to the _journal_index_type term in the IUCr Core CIF dictionary.
Corresponds to the _publ_contact_author term in the IUCr Core CIF dictionary.
The name and address of the author submitting the manuscript and data block. This is the person
contacted by the journal editorial staff. It is preferable to use the separate data items
_publ_contact_author_name and _publ_contact_author_address.
publ
Corresponds to the _publ_contact_author_address term in the IUCr Core CIF dictionary.
The address of the author submitting the manuscript and data block. This is the person contacted by
the journal editorial staff.
publ
Corresponds to the _publ_contact_author_email term in the IUCr Core CIF dictionary.
Email address in a form recognizable to international networks. The format of email addresses is
given in Section 3.4, Address Specification, of Internet Message Format, RFC 2822, P. Resnick (Editor),
Network Standards Group, April 2001.
publ
Corresponds to the _publ_contact_author_fax term in the IUCr Core CIF dictionary.
Facsimile telephone number of the author submitting the manuscript and data block. The recommended
style is the international dialing prefix, followed by the area code in parentheses, followed by the
local number with no spaces. The earlier convention of including the international dialing prefix in
parentheses is no longer recommended.
publ
Corresponds to the _publ_contact_author_id_iucr term in the IUCr Core CIF dictionary.
Identifier in the IUCr contact database of the author submitting the manuscript and data block.
This identifier may be available from the World Directory of Crystallographers (http://wdc.iucr.org).
publ
Corresponds to the _publ_contact_author_name term in the IUCr Core CIF dictionary.
The name of the author submitting the manuscript and data block. This is the person contacted by
the journal editorial staff.
publ
Corresponds to the _publ_contact_author_phone term in the IUCr Core CIF dictionary.
Telephone number of the author submitting the manuscript and data block. The recommended style is
the international dialing prefix, followed by the area code in parentheses, followed by the local number
and any extension number prefixed by 'x', with no spaces. The earlier convention of including the
international dialing prefix in parentheses is no longer recommended.
publ
Corresponds to the _publ_contact_letter term in the IUCr Core CIF dictionary.
A letter submitted to the journal editor by the contact author.
publ
Corresponds to the _publ_manuscript_creation term in the IUCr Core CIF dictionary.
A description of the wordprocessor package and computer used to create the wordprocessed
manuscript stored as _publ_manuscript_processed.
publ
Corresponds to the _publ_manuscript_processed term in the IUCr Core CIF dictionary.
The full manuscript of a paper (excluding possibly the figures and the tables) output in ASCII
characters from a word processor. Information about the generation of this data item must be specified
in the data item _publ_manuscript_creation.
publ
Corresponds to the _publ_manuscript_text term in the IUCr Core CIF dictionary.
The full manuscript of a paper (excluding figures and possibly the tables) output as standard ASCII
text.
publ
Corresponds to the _publ_requested_category term in the IUCr Core CIF dictionary.
The category of paper submitted. For submission to Acta Crystallographica Section C or Acta
Crystallographica Section E, ONLY those codes indicated for use with those journals should be used.
publ
FA
FI
FO
FM
CI
CO
CM
EI
EO
EM
QI
QO
QM
AD
SC
Corresponds to the _publ_requested_coeditor_name term in the IUCr Core CIF dictionary.
The name of the coeditor whom the authors would like to handle the submitted manuscript.
publ
Corresponds to the _publ_requested_journal term in the IUCr Core CIF dictionary.
The name of the journal to which the manuscript is being submitted.
publ
The sections of a manuscript if submitted in parts. As an alternative, see _publ_manuscript_text
and _publ_manuscript_processed. The _publ_section_exptl_prep, _publ_section_exptl_refinement and
_publ_section_exptl_solution items are preferred for separating the chemical preparation, refinement and
structure solution aspects of the experimental description.
publ
Corresponds to the _publ_section_title term in the IUCr Core CIF dictionary.
The sections of a manuscript if submitted in parts. As an alternative, see _publ_manuscript_text
and _publ_manuscript_processed. The _publ_section_exptl_prep, _publ_section_exptl_refinement and
_publ_section_exptl_solution items are preferred for separating the chemical preparation, refinement and
structure solution aspects of the experimental description.
publ
Corresponds to the _publ_section_synopsis term in the IUCr Core CIF dictionary.
The sections of a manuscript if submitted in parts. As an alternative, see _publ_manuscript_text
and _publ_manuscript_processed. The _publ_section_exptl_prep, _publ_section_exptl_refinement and
_publ_section_exptl_solution items are preferred for separating the chemical preparation, refinement and
structure solution aspects of the experimental description.
publ
Corresponds to the _publ_section_abstract term in the IUCr Core CIF dictionary.
The sections of a manuscript if submitted in parts. As an alternative, see _publ_manuscript_text
and _publ_manuscript_processed. The _publ_section_exptl_prep, _publ_section_exptl_refinement and
_publ_section_exptl_solution items are preferred for separating the chemical preparation, refinement and
structure solution aspects of the experimental description.
publ
Corresponds to the _publ_section_introduction term in the IUCr Core CIF dictionary.
The sections of a manuscript if submitted in parts. As an alternative, see _publ_manuscript_text
and _publ_manuscript_processed. The _publ_section_exptl_prep, _publ_section_exptl_refinement and
_publ_section_exptl_solution items are preferred for separating the chemical preparation, refinement and
structure solution aspects of the experimental description.
publ
Corresponds to the _publ_section_experimental term in the IUCr Core CIF dictionary.
The sections of a manuscript if submitted in parts. As an alternative, see _publ_manuscript_text
and _publ_manuscript_processed. The _publ_section_exptl_prep, _publ_section_exptl_refinement and
_publ_section_exptl_solution items are preferred for separating the chemical preparation, refinement and
structure solution aspects of the experimental description.
publ
Corresponds to the _publ_section_exptl_prep term in the IUCr Core CIF dictionary.
The sections of a manuscript if submitted in parts. As an alternative, see _publ_manuscript_text
and _publ_manuscript_processed. The _publ_section_exptl_prep, _publ_section_exptl_refinement and
_publ_section_exptl_solution items are preferred for separating the chemical preparation, refinement and
structure solution aspects of the experimental description.
publ
Corresponds to the _publ_section_exptl_refinement term in the IUCr Core CIF dictionary.
The sections of a manuscript if submitted in parts. As an alternative, see _publ_manuscript_text
and _publ_manuscript_processed. The _publ_section_exptl_prep, _publ_section_exptl_refinement and
_publ_section_exptl_solution items are preferred for separating the chemical preparation, refinement and
structure solution aspects of the experimental description.
publ
Corresponds to the _publ_section_exptl_solution term in the IUCr Core CIF dictionary.
The sections of a manuscript if submitted in parts. As an alternative, see _publ_manuscript_text
and _publ_manuscript_processed. The _publ_section_exptl_prep, _publ_section_exptl_refinement and
_publ_section_exptl_solution items are preferred for separating the chemical preparation, refinement and
structure solution aspects of the experimental description.
publ
Corresponds to the _publ_section_discussion term in the IUCr Core CIF dictionary.
The sections of a manuscript if submitted in parts. As an alternative, see _publ_manuscript_text
and _publ_manuscript_processed. The _publ_section_exptl_prep, _publ_section_exptl_refinement and
_publ_section_exptl_solution items are preferred for separating the chemical preparation, refinement and
structure solution aspects of the experimental description.
publ
Corresponds to the _publ_section_acknowledgements term in the IUCr Core CIF dictionary.
The sections of a manuscript if submitted in parts. As an alternative, see _publ_manuscript_text
and _publ_manuscript_processed. The _publ_section_exptl_prep, _publ_section_exptl_refinement and
_publ_section_exptl_solution items are preferred for separating the chemical preparation, refinement and
structure solution aspects of the experimental description.
publ
Corresponds to the _publ_section_references term in the IUCr Core CIF dictionary.
The sections of a manuscript if submitted in parts. As an alternative, see _publ_manuscript_text
and _publ_manuscript_processed. The _publ_section_exptl_prep, _publ_section_exptl_refinement and
_publ_section_exptl_solution items are preferred for separating the chemical preparation, refinement and
structure solution aspects of the experimental description.
publ
Corresponds to the _publ_section_related_literature term in the IUCr Core CIF dictionary.
The sections of a manuscript if submitted in parts. As an alternative, see _publ_manuscript_text
and _publ_manuscript_processed. The _publ_section_exptl_prep, _publ_section_exptl_refinement and
_publ_section_exptl_solution items are preferred for separating the chemical preparation, refinement and
structure solution aspects of the experimental description.
publ
Corresponds to the _publ_section_figure_captions term in the IUCr Core CIF dictionary.
The sections of a manuscript if submitted in parts. As an alternative, see _publ_manuscript_text
and _publ_manuscript_processed. The _publ_section_exptl_prep, _publ_section_exptl_refinement and
_publ_section_exptl_solution items are preferred for separating the chemical preparation, refinement and
structure solution aspects of the experimental description.
publ
Corresponds to the _publ_section_table_legends term in the IUCr Core CIF dictionary.
The sections of a manuscript if submitted in parts. As an alternative, see _publ_manuscript_text
and _publ_manuscript_processed. The _publ_section_exptl_prep, _publ_section_exptl_refinement and
_publ_section_exptl_solution items are preferred for separating the chemical preparation, refinement and
structure solution aspects of the experimental description.
publ
Corresponds to the _publ_section_keywords term in the IUCr Core CIF dictionary.
Corresponds to the _publ_author_address term in the IUCr Core CIF dictionary.
The address of a publication author. If there is more than one author, this will be looped with
_publ_author_name.
publ_author
Corresponds to the _publ_author_email term in the IUCr Core CIF dictionary.
The email address of a publication author. If there is more than one author, this will be looped
with _publ_author_name. The format of email addresses is given in Section 3.4, Address Specification,
of Internet Message Format, RFC 2822, P. Resnick (Editor), Network Standards Group, April 2001.
publ_author
Corresponds to the _publ_author_id_iucr term in the IUCr Core CIF dictionary.
Identifier in the IUCr contact database of a publication author. This identifier may be available
from the World Directory of Crystallographers (http://wdc.iucr.org).
publ_author
Corresponds to the _publ_author_name term in the IUCr Core CIF dictionary.
The name of a publication author. If there are multiple authors, this will be looped with
_publ_author_address. The family name(s), followed by a comma and including any dynastic components,
precedes the first names or initials.
publ_author
Corresponds to the _publ_body_contents term in the IUCr Core CIF dictionary.
A text section of a paper.
publ_body
Corresponds to the _publ_body_element term in the IUCr Core CIF dictionary.
The functional role of the associated text section.
publ_body
section
subsection
subsubsection
appendix
footnote
Corresponds to the _publ_body_format term in the IUCr Core CIF dictionary.
Code indicating the appropriate typesetting conventions for accented characters and special symbols
in the text section.
publ_body
ascii
cif
latex
rtf
sgml
tex
troff
Corresponds to the _publ_body_label term in the IUCr Core CIF dictionary.
Code identifying the section of text. The combination of this with _publ_body_element must be
unique.
publ_body
Corresponds to the _publ_body_title term in the IUCr Core CIF dictionary.
Title of the associated section of text.
publ_body
The largest and smallest values and the rootmeansquare deviation, in electrons per angstrom
cubed, of the final difference electron density. The *_rms value is measured with respect to the
arithmetic mean density and is derived from summations over each grid point in the asymmetric unit of
the cell. This quantity is useful for assessing the significance of *_min and *_max values, and also for
defining suitable contour levels.
refine
Corresponds to the _refine_diff_density_max term in the IUCr Core CIF dictionary.
The largest and smallest values and the rootmeansquare deviation, in electrons per angstrom
cubed, of the final difference electron density. The *_rms value is measured with respect to the
arithmetic mean density and is derived from summations over each grid point in the asymmetric unit of
the cell. This quantity is useful for assessing the significance of *_min and *_max values, and also for
defining suitable contour levels.
refine
Corresponds to the _refine_diff_density_min term in the IUCr Core CIF dictionary.
The largest and smallest values and the rootmeansquare deviation, in electrons per angstrom
cubed, of the final difference electron density. The *_rms value is measured with respect to the
arithmetic mean density and is derived from summations over each grid point in the asymmetric unit of
the cell. This quantity is useful for assessing the significance of *_min and *_max values, and also for
defining suitable contour levels.
refine
Corresponds to the _refine_diff_density_rms term in the IUCr Core CIF dictionary.
Corresponds to the _refine_ls_abs_structure_details term in the IUCr Core CIF dictionary.
The nature of the absolute structure and how it was determined.
refine
Corresponds to the _refine_ls_abs_structure_flack term in the IUCr Core CIF dictionary.
The measure of absolute structure as defined by Flack (1983). For centrosymmetric structures, the
only permitted value, if the data name is present, is 'inapplicable', represented by '.' . For
noncentrosymmetric structures, the value must lie in the 99.97% Gaussian confidence interval 3u =< x
=< 1 + 3u and a standard uncertainty (e.s.d.) u must be supplied. The _enumeration_range of 0.0:1.0
is correctly interpreted as meaning (0.0  3u) =< x =< (1.0 + 3u). Ref: Flack, H. D. (1983). Acta
Cryst. A39, 876881.
refine
Corresponds to the _refine_ls_abs_structure_rogers term in the IUCr Core CIF dictionary.
The measure of absolute structure as defined by Rogers (1981). The value must lie in the 99.97%
Gaussian confidence interval 1 3u =< \h =< 1 + 3u and a standard uncertainty (e.s.d.) u must be
supplied. The _enumeration_range of 1.0:1.0 is correctly interpreted as meaning (1.0  3u) =< \h =<
(1.0 + 3u). Ref: Rogers, D. (1981). Acta Cryst. A37, 734741.
refine
Corresponds to the _refine_ls_d_res_high term in the IUCr Core CIF dictionary.
The smallest value in angstroms of the interplanar spacings of the reflections used in the
refinement. This is called the highest resolution.
refine
Corresponds to the _refine_ls_d_res_low term in the IUCr Core CIF dictionary.
The largest value in angstroms of the interplanar spacings of the reflections used in the
refinement. This is called the lowest resolution.
refine
Corresponds to the _refine_ls_extinction_coef term in the IUCr Core CIF dictionary.
The extinction coefficient used to calculate the correction factor applied to the structurefactor
data. The nature of the extinction coefficient is given in the definitions of
_refine_ls_extinction_expression and _refine_ls_extinction_method. For the 'Zachariasen' method it is
the r* value; for the 'BeckerCoppens type 1 isotropic' method it is the 'g' value and for
'BeckerCoppens type 2 isotropic' corrections it is the 'rho' value. Note that the magnitude of these
values is usually of the order of 10000. Ref: Becker, P. J. & Coppens, P. (1974). Acta Cryst. A30,
129147, 148153. Zachariasen, W. H. (1967). Acta Cryst. 23, 558564. Larson, A. C. (1967). Acta Cryst.
23, 664665.
refine
Corresponds to the _refine_ls_extinction_expression term in the IUCr Core CIF dictionary.
A description of or reference to the extinctioncorrection equation used to apply the data item
_refine_ls_extinction_coef. This information must be sufficient to reproduce the extinctioncorrection
factors applied to the structure factors.
refine
Corresponds to the _refine_ls_extinction_method term in the IUCr Core CIF dictionary.
A description of the extinctioncorrection method applied. This description should include
information about the correction method, either 'BeckerCoppens' or 'Zachariasen'. The latter is
sometimes referred to as the 'Larson' method even though it employs Zachariasen's formula. The
BeckerCoppens procedure is referred to as 'type 1' when correcting secondary extinction dominated by
the mosaic spread; as 'type 2' when secondary extinction is dominated by particle size and includes a
primary extinction component; and as 'mixed' when there is a mixture of types 1 and 2. For the
BeckerCoppens method, it is also necessary to set the mosaic distribution as either 'Gaussian' or
'Lorentzian' and the nature of the extinction as 'isotropic' or 'anisotropic'. Note that if either the
'mixed' or 'anisotropic' corrections are applied, the multiple coefficients cannot be contained in
*_extinction_coef and must be listed in _refine_special_details. Ref: Becker, P. J. & Coppens, P.
(1974). Acta Cryst. A30, 129147, 148153. Zachariasen, W. H. (1967). Acta Cryst. 23, 558564. Larson,
A. C. (1967). Acta Cryst. 23, 664665.
refine
Corresponds to the _refine_ls_f_calc_details term in the IUCr Core CIF dictionary.
Details concerning the evaluation of the structure factors using the expression given in
_refine_ls_F_calc_formula.
refine
Corresponds to the _refine_ls_f_calc_formula term in the IUCr Core CIF dictionary.
Analytical expression used to calculate the structure factors.
refine
Corresponds to the _refine_ls_f_calc_precision term in the IUCr Core CIF dictionary.
This item gives an estimate of the precision resulting from the numerical approximations made
during the evaluation of the structure factors using the expression given in _refine_ls_F_calc_formula
following the method outlined in _refine_ls_F_calc_details. For Xray diffraction the result is given in
electrons.
refine
Corresponds to the _refine_ls_goodness_of_fit_all term in the IUCr Core CIF dictionary.
The leastsquares goodnessoffit parameter S for all reflections after the final cycle of
refinement. Ideally, account should be taken of parameters restrained in the leastsquares refinement.
See also _refine_ls_restrained_S_ definitions. { sum { w [ Y(obs)  Y(calc) ]^2^ } }^1/2^ S = {
 } { Nref  Nparam } Y(obs) = the observed coefficients (see
_refine_ls_structure_factor_coef) Y(calc) = the calculated coefficients (see
_refine_ls_structure_factor_coef) w = the leastsquares reflection weight [1/(u^2^)] u = the standard
uncertainty Nref = the number of reflections used in the refinement Nparam = the number of refined
parameters and the sum is taken over the specified reflections
refine
Corresponds to the _refine_ls_goodness_of_fit_gt term in the IUCr Core CIF dictionary.
The leastsquares goodnessoffit parameter S for significantly intense reflections (see
_reflns_threshold_expression) after the final cycle of refinement. Ideally, account should be taken of
parameters restrained in the leastsquares refinement. See also _refine_ls_restrained_S_ definitions. {
sum { w [ Y(obs)  Y(calc) ]^2^ } }^1/2^ S = {  } { Nref  Nparam }
Y(obs) = the observed coefficients (see _refine_ls_structure_factor_coef) Y(calc) = the calculated
coefficients (see _refine_ls_structure_factor_coef) w = the leastsquares reflection weight [1/(u^2^)] u
= standard uncertainty Nref = the number of reflections used in the refinement Nparam = the number of
refined parameters and the sum is taken over the specified reflections
refine
Corresponds to the _refine_ls_goodness_of_fit_obs term in the IUCr Core CIF dictionary.
The leastsquares goodnessoffit parameter S for observed reflections (see
_reflns_observed_criterion) after the final cycle of refinement. Ideally, account should be taken of
parameters restrained in the leastsquares refinement. See also _refine_ls_restrained_S_ definitions. {
sum { w [ Y(obs)  Y(calc) ]^2^ } }^1/2^ S = {  } { Nref  Nparam }
Y(obs) = the observed coefficients (see _refine_ls_structure_factor_coef) Y(calc) = the calculated
coefficients (see _refine_ls_structure_factor_coef) w = the leastsquares reflection weight [1/(u^2^)] u
= standard uncertainty (e.s.d.) Nref = the number of reflections used in the refinement Nparam = the
number of refined parameters and the sum is taken over the specified reflections
refine
Corresponds to the _refine_ls_goodness_of_fit_ref term in the IUCr Core CIF dictionary.
The leastsquares goodnessoffit parameter S for all reflections included in the refinement after
the final cycle of refinement. Ideally, account should be taken of parameters restrained in the
leastsquares refinement. See also _refine_ls_restrained_S_ definitions. { sum  w  Y(obs)  Y(calc)
^2^  }^1/2^ S = {  } { Nref  Nparam } Y(obs) = the observed
coefficients (see _refine_ls_structure_factor_coef) Y(calc) = the calculated coefficients (see
_refine_ls_structure_factor_coef) w = the leastsquares reflection weight [1/(u^2^)] u = standard
uncertainty Nref = the number of reflections used in the refinement Nparam = the number of refined
parameters and the sum is taken over the specified reflections
refine
Corresponds to the _refine_ls_hydrogen_treatment term in the IUCr Core CIF dictionary.
Treatment of hydrogen atoms in the leastsquares refinement.
refine
refall
refxyz
refU
noref
constr
mixed
undef
Corresponds to the _refine_ls_matrix_type term in the IUCr Core CIF dictionary.
Type of matrix used to accumulate the leastsquares derivatives.
refine
full
fullcycle
atomblock
userblock
diagonal
sparse
Corresponds to the _refine_ls_number_constraints term in the IUCr Core CIF dictionary.
The number of constrained (nonrefined or dependent) parameters in the leastsquares process. These
may be due to symmetry or any other constraint process (e.g. rigidbody refinement). See also
_atom_site_constraints and _atom_site_refinement_flags. A general description of constraints may appear
in _refine_special_details.
refine
Corresponds to the _refine_ls_number_parameters term in the IUCr Core CIF dictionary.
The number of parameters refined in the leastsquares process. If possible, this number should
include some contribution from the restrained parameters. The restrained parameters are distinct from
the constrained parameters (where one or more parameters are linearly dependent on the refined value of
another). Leastsquares restraints often depend on geometry or energy considerations and this makes
their direct contribution to this number, and to the goodnessoffit calculation, difficult to assess.
refine
Corresponds to the _refine_ls_number_reflns term in the IUCr Core CIF dictionary.
The number of unique reflections contributing to the leastsquares refinement calculation.
refine
Corresponds to the _refine_ls_number_restraints term in the IUCr Core CIF dictionary.
The number of restrained parameters. These are parameters which are not directly dependent on
another refined parameter. Restrained parameters often involve geometry or energy dependencies. See also
_atom_site_constraints and _atom_site_refinement_flags. A general description of refinement constraints
may appear in _refine_special_details.
refine
Corresponds to the _refine_ls_r_factor_all term in the IUCr Core CIF dictionary.
Residual factor for all reflections satisfying the resolution limits established by
_refine_ls_d_res_high and _refine_ls_d_res_low. This is the conventional R factor. See also
_refine_ls_wR_factor_ definitions. sum  F(obs)  F(calc)  R =  sum  F(obs) 
F(obs) = the observed structurefactor amplitudes F(calc) = the calculated structurefactor amplitudes
and the sum is taken over the specified reflections
refine
Corresponds to the _refine_ls_r_factor_gt term in the IUCr Core CIF dictionary.
Residual factor for the reflections (with number given by _reflns_number_gt) judged significantly
intense (i.e. satisfying the threshold specified by _reflns_threshold_expression) and included in the
refinement. The reflections also satisfy the resolution limits established by _refine_ls_d_res_high and
_refine_ls_d_res_low. This is the conventional R factor. See also _refine_ls_wR_factor_ definitions. sum
 F(obs)  F(calc)  R =  sum  F(obs)  F(obs) = the observed structurefactor
amplitudes F(calc) = the calculated structurefactor amplitudes and the sum is taken over the specified
reflections
refine
Corresponds to the _refine_ls_r_factor_obs term in the IUCr Core CIF dictionary.
Residual factor for the reflections classified as 'observed' (see _reflns_observed_criterion) and
included in the refinement. The reflections also satisfy the resolution limits established by
_refine_ls_d_res_high and _refine_ls_d_res_low. This is the conventional R factor. See also
_refine_ls_wR_factor_ definitions. sum  F(obs)  F(calc)  R =  sum  F(obs) 
F(obs) = the observed structurefactor amplitudes F(calc) = the calculated structurefactor amplitudes
and the sum is taken over the specified reflections
refine
Corresponds to the _refine_ls_r_fsqd_factor term in the IUCr Core CIF dictionary.
Residual factor R(Fsqd), calculated on the squared amplitudes of the observed and calculated
structure factors, for significantly intense reflections (satisfying _reflns_threshold_expression) and
included in the refinement. The reflections also satisfy the resolution limits established by
_refine_ls_d_res_high and _refine_ls_d_res_low. sum  F(obs)^2^  F(calc)^2^  R(Fsqd) =
 sum F(obs)^2^ F(obs)^2^ = squares of the observed structurefactor
amplitudes F(calc)^2^ = squares of the calculated structurefactor amplitudes and the sum is taken over
the specified reflections
refine
Corresponds to the _refine_ls_r_i_factor term in the IUCr Core CIF dictionary.
Residual factor R(I) for significantly intense reflections (satisfying
_reflns_threshold_expression) and included in the refinement. This is most often calculated in Rietveld
refinements against powder data, where it is referred to as R~B~ or R~Bragg~. sum  I(obs)  I(calc) 
R(I) =  sum  I(obs)  I(obs) = the net observed intensities I(calc) = the net
calculated intensities and the sum is taken over the specified reflections
refine
Corresponds to the _refine_ls_restrained_s_all term in the IUCr Core CIF dictionary.
The leastsquares goodnessoffit parameter S' for all reflections after the final cycle of
leastsquares refinement. This parameter explicitly includes the restraints applied in the leastsquares
process. See also _refine_ls_goodness_of_fit_ definitions. {sum { w [ Y(obs)  Y(calc) ]^2^ } }^1/2^ { +
sum~r~ { w~r~ [ P(calc)  P(targ) ]^2^ } } S' = {  } {
N~ref~ + N~restr~  N~param~ } Y(obs) = the observed coefficients (see _refine_ls_structure_factor_coef)
Y(calc) = the calculated coefficients (see _refine_ls_structure_factor_coef) w = the leastsquares
reflection weight [1/square of standard uncertainty (e.s.d.)] P(calc) = the calculated restraint values
P(targ) = the target restraint values w~r~ = the restraint weight N~ref~ = the number of reflections
used in the refinement (see _refine_ls_number_reflns) N~restr~ = the number of restraints (see
_refine_ls_number_restraints) N~param~ = the number of refined parameters (see
_refine_ls_number_parameters) sum is taken over the specified reflections sum~r~ is taken over the
restraints
refine
Corresponds to the _refine_ls_restrained_s_gt term in the IUCr Core CIF dictionary.
The leastsquares goodnessoffit parameter S' for significantly intense reflections (satisfying
_reflns_threshold_expression) after the final cycle of leastsquares refinement. This parameter
explicitly includes the restraints applied in the leastsquares process. See also
_refine_ls_goodness_of_fit_ definitions. {sum { w [ Y(obs)  Y(calc) ]^2^ } }^1/2^ { + sum~r~ { w~r~ [
P(calc)  P(targ) ]^2^ } } S' = {  } { N~ref~ +
N~restr~  N~param~ } Y(obs) = the observed coefficients (see _refine_ls_structure_factor_coef) Y(calc)
= the calculated coefficients (see _refine_ls_structure_factor_coef) w = the leastsquares reflection
weight [1/square of standard uncertainty (e.s.d.)] P(calc) = the calculated restraint values P(targ) =
the target restraint values w~r~ = the restraint weight N~ref~ = the number of reflections used in the
refinement (see _refine_ls_number_reflns) N~restr~ = the number of restraints (see
_refine_ls_number_restraints) N~param~ = the number of refined parameters (see
_refine_ls_number_parameters) sum is taken over the specified reflections sum~r~ is taken over the
restraints
refine
Corresponds to the _refine_ls_restrained_s_obs term in the IUCr Core CIF dictionary.
The leastsquares goodnessoffit parameter S' for observed reflections after the final cycle of
leastsquares refinement. This parameter explicitly includes the restraints applied in the leastsquares
process. See also _refine_ls_goodness_of_fit_ definitions. {sum { w [ Y(obs)  Y(calc) ]^2^ } }^1/2^ { +
sum~r~ { w~r~ [ P(calc)  P(targ) ]^2^ } } S' = {  } {
N~ref~ + N~restr~  N~param~ } Y(obs) = the observed coefficients (see _refine_ls_structure_factor_coef)
Y(calc) = the calculated coefficients (see _refine_ls_structure_factor_coef) w = the leastsquares
reflection weight [1/square of standard uncertainty (e.s.d.)] P(calc) = the calculated restraint values
P(targ) = the target restraint values w~r~ = the restraint weight N~ref~ = the number of reflections
used in the refinement (see _refine_ls_number_reflns) N~restr~ = the number of restraints (see
_refine_ls_number_restraints) N~param~ = the number of refined parameters (see
_refine_ls_number_parameters) sum is taken over the specified reflections sum~r~ is taken over the
restraints
refine
Corresponds to the _refine_ls_shift/esd_max term in the IUCr Core CIF dictionary.
The largest ratio of the final leastsquares parameter shift to the final standard uncertainty
(s.u., formerly described as estimated standard deviation, e.s.d.).
refine
Corresponds to the _refine_ls_shift/esd_mean term in the IUCr Core CIF dictionary.
The average ratio of the final leastsquares parameter shift to the final standard uncertainty
(s.u., formerly described as estimated standard deviation, e.s.d.).
refine
Corresponds to the _refine_ls_shift/su_max term in the IUCr Core CIF dictionary.
The largest ratio of the final leastsquares parameter shift to the final standard uncertainty.
refine
Corresponds to the _refine_ls_shift/su_max_lt term in the IUCr Core CIF dictionary.
An upper limit for the largest ratio of the final leastsquares parameter shift to the final
standard uncertainty. This item is used when the largest value of the shift divided by the final
standard uncertainty is too small to measure.
refine
Corresponds to the _refine_ls_shift/su_mean term in the IUCr Core CIF dictionary.
The average ratio of the final leastsquares parameter shift to the final standard uncertainty.
refine
Corresponds to the _refine_ls_shift/su_mean_lt term in the IUCr Core CIF dictionary.
An upper limit for the average ratio of the final leastsquares parameter shift to the final
standard uncertainty. This item is used when the average value of the shift divided by the final
standard uncertainty is too small to measure.
refine
Corresponds to the _refine_ls_structure_factor_coef term in the IUCr Core CIF dictionary.
Structurefactor coefficient F, F^2^ or I used in the leastsquares refinement process.
refine
F
Fsqd
Inet
Corresponds to the _refine_ls_weighting_details term in the IUCr Core CIF dictionary.
A description of special aspects of the weighting scheme used in the leastsquares refinement. Used
to describe the weighting when the value of _refine_ls_weighting_scheme is specified as 'calc'.
refine
Corresponds to the _refine_ls_weighting_scheme term in the IUCr Core CIF dictionary.
The weighting scheme applied in the leastsquares process. The standard code may be followed by a
description of the weight (but see _refine_ls_weighting_details for a preferred approach).
refine
sigma
unit
calc
Corresponds to the _refine_ls_wr_factor_all term in the IUCr Core CIF dictionary.
Weighted residual factors for all reflections. The reflections also satisfy the resolution limits
established by _refine_ls_d_res_high and _refine_ls_d_res_low. See also the _refine_ls_R_factor_
definitions. ( sum w [ Y(obs)  Y(calc) ]^2^ )^1/2^ wR = (  ) ( sum w
Y(obs)^2^ ) Y(obs) = the observed amplitude specified by _refine_ls_structure_factor_coef Y(calc) = the
calculated amplitude specified by _refine_ls_structure_factor_coef w = the leastsquares weight and the
sum is taken over the specified reflections
refine
Corresponds to the _refine_ls_wr_factor_gt term in the IUCr Core CIF dictionary.
Weighted residual factors for significantly intense reflections (satisfying
_reflns_threshold_expression) included in the refinement. The reflections also satisfy the resolution
limits established by _refine_ls_d_res_high and _refine_ls_d_res_low. See also the _refine_ls_R_factor_
definitions. ( sum w [ Y(obs)  Y(calc) ]^2^ )^1/2^ wR = (  ) ( sum w
Y(obs)^2^ ) Y(obs) = the observed amplitude specified by _refine_ls_structure_factor_coef Y(calc) = the
calculated amplitude specified by _refine_ls_structure_factor_coef w = the leastsquares weight and the
sum is taken over the specified reflections
refine
Corresponds to the _refine_ls_wr_factor_obs term in the IUCr Core CIF dictionary.
Weighted residual factors for the reflections classified as 'observed' (see
_reflns_observed_criterion) and included in the refinement. The reflections also satisfy the resolution
limits established by _refine_ls_d_res_high and _refine_ls_d_res_low. See also the _refine_ls_R_factor_
definitions. ( sum w [ Y(obs)  Y(calc) ]^2^ )^1/2^ wR = (  ) ( sum w
Y(obs)^2^ ) Y(obs) = the observed amplitude specified by _refine_ls_structure_factor_coef Y(calc) = the
calculated amplitude specified by _refine_ls_structure_factor_coef w = the leastsquares weight and the
sum is taken over the specified reflections
refine
Corresponds to the _refine_ls_wr_factor_ref term in the IUCr Core CIF dictionary.
Weighted residual factors for all reflections included in the refinement. The reflections also
satisfy the resolution limits established by _refine_ls_d_res_high and _refine_ls_d_res_low. See also
the _refine_ls_R_factor_ definitions. ( sum w [ Y(obs)  Y(calc) ]^2^ )^1/2^ wR = (
 ) ( sum w Y(obs)^2^ ) Y(obs) = the observed amplitude specified by
_refine_ls_structure_factor_coef Y(calc) = the calculated amplitude specified by
_refine_ls_structure_factor_coef w = the leastsquares weight and the sum is taken over the specified
reflections
refine
Corresponds to the _refine_special_details term in the IUCr Core CIF dictionary.
Description of special aspects of the refinement process.
refine
Corresponds to the _refine_ls_class_code term in the IUCr Core CIF dictionary.
The code identifying a certain reflection class. This code must match a _reflns_class_code.
refine_ls_class
Corresponds to the _refine_ls_class_d_res_high term in the IUCr Core CIF dictionary.
For each reflection class, the highest resolution in angstroms for the reflections used in the
refinement. This is the lowest d value in a reflection class.
refine_ls_class
Corresponds to the _refine_ls_class_d_res_low term in the IUCr Core CIF dictionary.
For each reflection class, the lowest resolution in angstroms for the reflections used in the
refinement. This is the highest d value in a reflection class.
refine_ls_class
For each reflection class, the residual factors for all reflections, and for significantly intense
reflections (see _reflns_threshold_expression), included in the refinement. The reflections also satisfy
the resolution limits established by _refine_ls_class_d_res_high and _refine_ls_class_d_res_low. This is
the conventional R factor. sum  F(obs)  F(calc)  R =  sum  F(obs)  F(obs) =
the observed structurefactor amplitudes F(calc) = the calculated structurefactor amplitudes and the
sum is taken over the reflections of this class. See also _refine_ls_class_wR_factor_all definitions.
refine_ls_class
Corresponds to the _refine_ls_class_r_factor_all term in the IUCr Core CIF dictionary.
For each reflection class, the residual factors for all reflections, and for significantly intense
reflections (see _reflns_threshold_expression), included in the refinement. The reflections also satisfy
the resolution limits established by _refine_ls_class_d_res_high and _refine_ls_class_d_res_low. This is
the conventional R factor. sum  F(obs)  F(calc)  R =  sum  F(obs)  F(obs) =
the observed structurefactor amplitudes F(calc) = the calculated structurefactor amplitudes and the
sum is taken over the reflections of this class. See also _refine_ls_class_wR_factor_all definitions.
refine_ls_class
Corresponds to the _refine_ls_class_r_factor_gt term in the IUCr Core CIF dictionary.
Corresponds to the _refine_ls_class_r_fsqd_factor term in the IUCr Core CIF dictionary.
For each reflection class, the residual factor R(F^2^) calculated on the squared amplitudes of the
observed and calculated structure factors for the reflections judged significantly intense (i.e.
satisfying the threshold specified by _reflns_threshold_expression) and included in the refinement. The
reflections also satisfy the resolution limits established by _refine_ls_class_d_res_high and
_refine_ls_class_d_res_low. sum  F(obs)^2^  F(calc)^2^  R(Fsqd) =  sum
F(obs)^2^ F(obs)^2^ = squares of the observed structurefactor amplitudes F(calc)^2^ = squares of the
calculated structurefactor amplitudes and the sum is taken over the reflections of this class.
refine_ls_class
Corresponds to the _refine_ls_class_r_i_factor term in the IUCr Core CIF dictionary.
For each reflection class, the residual factor R(I) for the reflections judged significantly
intense (i.e. satisfying the threshold specified by _reflns_threshold_expression) and included in the
refinement. This is most often calculated in Rietveld refinements against powder data, where it is
referred to as R~B~ or R~Bragg~. sum  I(obs)  I(calc)  R(I) =  sum  I(obs) 
I(obs) = the net observed intensities I(calc) = the net calculated intensities and the sum is taken over
the reflections of this class.
refine_ls_class
Corresponds to the _refine_ls_class_wr_factor_all term in the IUCr Core CIF dictionary.
For each reflection class, the weighted residual factors for all reflections included in the
refinement. The reflections also satisfy the resolution limits established by
_refine_ls_class_d_res_high and _refine_ls_class_d_res_low. ( sum w [ Y(obs)  Y(calc) ]^2^ )^1/2^ wR =
(  ) ( sum w Y(obs)^2^ ) Y(obs) = the observed amplitudes specified by
_refine_ls_structure_factor_coef Y(calc) = the calculated amplitudes specified by
_refine_ls_structure_factor_coef w = the leastsquares weights and the sum is taken over the reflections
of this class. See also _refine_ls_class_R_factor_ definitions.
refine_ls_class
The calculated and measured structurefactor component A (in electrons for Xray diffraction). A
=Fcos(phase)
refln
Corresponds to the _refln_a_calc term in the IUCr Core CIF dictionary.
The calculated and measured structurefactor component A (in electrons for Xray diffraction). A
=Fcos(phase)
refln
Corresponds to the _refln_a_meas term in the IUCr Core CIF dictionary.
The calculated and measured structurefactor component B (in electrons for Xray diffraction). B
=Fsin(phase)
refln
Corresponds to the _refln_b_calc term in the IUCr Core CIF dictionary.
The calculated and measured structurefactor component B (in electrons for Xray diffraction). B
=Fsin(phase)
refln
Corresponds to the _refln_b_meas term in the IUCr Core CIF dictionary.
Corresponds to the _refln_class_code term in the IUCr Core CIF dictionary.
The code identifying the class to which this reflection has been assigned. This code must match a
value of _reflns_class_code. Reflections may be grouped into classes for a variety of purposes. For
example, for modulated structures each reflection class may be defined by the number m=summ~i~, where
the m~i~ are the integer coefficients that, in addition to h,k,l, index the corresponding diffraction
vector in the basis defined for the reciprocal lattice.
refln
Corresponds to the _refln_crystal_id term in the IUCr Core CIF dictionary.
Code identifying each crystal if multiple crystals are used. Is used to link with _exptl_crystal_id
in the _exptl_crystal_ list.
refln
Corresponds to the _refln_d_spacing term in the IUCr Core CIF dictionary.
The d spacing in angstroms for this reflection. This is related to the (sin theta)/lambda value by
the expression _refln_d_spacing = 2/(_refln_sint/lambda)
refln
The calculated, measured and standard uncertainty (derived from measurement) of the structure
factors (in electrons for Xray diffraction).
refln
Corresponds to the _refln_f_calc term in the IUCr Core CIF dictionary.
The calculated, measured and standard uncertainty (derived from measurement) of the structure
factors (in electrons for Xray diffraction).
refln
Corresponds to the _refln_f_meas term in the IUCr Core CIF dictionary.
The calculated, measured and standard uncertainty (derived from measurement) of the structure
factors (in electrons for Xray diffraction).
refln
Corresponds to the _refln_f_sigma term in the IUCr Core CIF dictionary.
Calculated, measured and estimated standard uncertainty (derived from measurement) of the squared
structure factors (in electrons squared for Xray diffraction).
refln
Corresponds to the _refln_f_squared_calc term in the IUCr Core CIF dictionary.
Calculated, measured and estimated standard uncertainty (derived from measurement) of the squared
structure factors (in electrons squared for Xray diffraction).
refln
Corresponds to the _refln_f_squared_meas term in the IUCr Core CIF dictionary.
Calculated, measured and estimated standard uncertainty (derived from measurement) of the squared
structure factors (in electrons squared for Xray diffraction).
refln
Corresponds to the _refln_f_squared_sigma term in the IUCr Core CIF dictionary.
Corresponds to the _refln_include_status term in the IUCr Core CIF dictionary.
Classification of a reflection indicating its status with respect to inclusion in the refinement
and the calculation of R factors.
refln
o
<

x
h
l
Miller indices of the reflection. The values of the Miller indices in the REFLN category must
correspond to the cell defined by the cell lengths and cell angles in the CELL category.
refln
Corresponds to the _refln_index_h term in the IUCr Core CIF dictionary.
Miller indices of the reflection. The values of the Miller indices in the REFLN category must
correspond to the cell defined by the cell lengths and cell angles in the CELL category.
refln
Corresponds to the _refln_index_k term in the IUCr Core CIF dictionary.
Miller indices of the reflection. The values of the Miller indices in the REFLN category must
correspond to the cell defined by the cell lengths and cell angles in the CELL category.
refln
Corresponds to the _refln_index_l term in the IUCr Core CIF dictionary.
The calculated, measured and standard uncertainty (derived from measurement) of the intensity, all
in the same arbitrary units as _refln_intensity_meas.
refln
Corresponds to the _refln_intensity_calc term in the IUCr Core CIF dictionary.
The calculated, measured and standard uncertainty (derived from measurement) of the intensity, all
in the same arbitrary units as _refln_intensity_meas.
refln
Corresponds to the _refln_intensity_meas term in the IUCr Core CIF dictionary.
The calculated, measured and standard uncertainty (derived from measurement) of the intensity, all
in the same arbitrary units as _refln_intensity_meas.
refln
Corresponds to the _refln_intensity_sigma term in the IUCr Core CIF dictionary.
Corresponds to the _refln_mean_path_length_tbar term in the IUCr Core CIF dictionary.
Mean path length in millimetres through the crystal for this reflection.
refln
Corresponds to the _refln_observed_status term in the IUCr Core CIF dictionary.
Classification of a reflection indicating its status with respect to inclusion in the refinement
and the calculation of R factors.
refln
o
<

x
h
l
Corresponds to the _refln_phase_calc term in the IUCr Core CIF dictionary.
The calculated structurefactor phase in degrees.
refln
Corresponds to the _refln_phase_meas term in the IUCr Core CIF dictionary.
The measured structurefactor phase in degrees.
refln
Corresponds to the _refln_refinement_status term in the IUCr Core CIF dictionary.
Status of a reflection in the structurerefinement process.
refln
incl
excl
extn
Corresponds to the _refln_scale_group_code term in the IUCr Core CIF dictionary.
Code identifying the structurefactor scale. This code must correspond to one of the
_reflns_scale_group_code values.
refln
Corresponds to the _refln_sint/lambda term in the IUCr Core CIF dictionary.
The (sin theta)/lambda value in reciprocal angstroms for this reflection.
refln
Corresponds to the _refln_symmetry_epsilon term in the IUCr Core CIF dictionary.
The symmetry reinforcement factor corresponding to the number of times the reflection indices are
generated identically from the spacegroup symmetry operations.
refln
Corresponds to the _refln_symmetry_multiplicity term in the IUCr Core CIF dictionary.
The number of reflections symmetryequivalent under the Laue symmetry to the present reflection. In
the Laue symmetry, Friedel opposites (h k l and h k l) are equivalent. Tables of symmetryequivalent
reflections are available in International Tables for Crystallography Volume A (2002), Chapter 10.1.
refln
Corresponds to the _refln_wavelength term in the IUCr Core CIF dictionary.
The mean wavelength in angstroms of the radiation used to measure this reflection. This is an
important parameter for data collected using energydispersive detectors or the Laue method.
refln
Corresponds to the _refln_wavelength_id term in the IUCr Core CIF dictionary.
Code identifying the wavelength in the _diffrn_radiation_ list. See
_diffrn_radiation_wavelength_id.
refln
The highest and lowest resolution in angstroms for the reflections. These are the smallest and
largest d values.
reflns
Corresponds to the _reflns_d_resolution_high term in the IUCr Core CIF dictionary.
The highest and lowest resolution in angstroms for the reflections. These are the smallest and
largest d values.
reflns
Corresponds to the _reflns_d_resolution_low term in the IUCr Core CIF dictionary.
Corresponds to the _reflns_friedel_coverage term in the IUCr Core CIF dictionary.
The proportion of Friedelrelated reflections present in the number of 'independent' reflections
specified by the item _reflns_number_total. This proportion is calculated as the ratio: [N(crystal
class)  N(Laue symmetry)] / N(Laue symmetry) where, working from the _diffrn_refln_ list, N(crystal
class) is the number of reflections obtained on averaging under the symmetry of the crystal class N(Laue
symmetry) is the number of reflections obtained on averaging under the Laue symmetry. Examples: (a) For
centrosymmetric structures, _reflns_Friedel_coverage is necessarily equal to 0.0 as the crystal class is
identical to the Laue symmetry. (b) For wholesphere data for a crystal in the space group P1,
_reflns_Friedel_coverage is equal to 1.0, as no reflection h k l is equivalent to h k l in the
crystal class and all Friedel pairs {h k l; h k l} have been measured. (c) For wholesphere data in
space group Pmm2, _reflns_Friedel_coverage will be < 1.0 because although reflections h k l and h k
l are not equivalent when h k l indices are nonzero, they are when l=0. (d) For a crystal in the space
group Pmm2, measurements of the two inequivalent octants h >= 0, k >=0, l lead to the same value
as in (c), whereas measurements of the two equivalent octants h >= 0, k, l >= 0 will lead to a
value of zero for _reflns_Friedel_coverage.
reflns
Miller indices limits for the reported reflections. These need not be the same as the
_diffrn_reflns_limit_ values.
reflns
Corresponds to the _reflns_limit_h_max term in the IUCr Core CIF dictionary.
Miller indices limits for the reported reflections. These need not be the same as the
_diffrn_reflns_limit_ values.
reflns
Corresponds to the _reflns_limit_h_min term in the IUCr Core CIF dictionary.
Miller indices limits for the reported reflections. These need not be the same as the
_diffrn_reflns_limit_ values.
reflns
Corresponds to the _reflns_limit_k_max term in the IUCr Core CIF dictionary.
Miller indices limits for the reported reflections. These need not be the same as the
_diffrn_reflns_limit_ values.
reflns
Corresponds to the _reflns_limit_k_min term in the IUCr Core CIF dictionary.
Miller indices limits for the reported reflections. These need not be the same as the
_diffrn_reflns_limit_ values.
reflns
Corresponds to the _reflns_limit_l_max term in the IUCr Core CIF dictionary.
Miller indices limits for the reported reflections. These need not be the same as the
_diffrn_reflns_limit_ values.
reflns
Corresponds to the _reflns_limit_l_min term in the IUCr Core CIF dictionary.
Corresponds to the _reflns_number_gt term in the IUCr Core CIF dictionary.
The number of reflections in the _refln_ list (not the _diffrn_refln_ list) that are significantly
intense, satisfying the criterion specified by _reflns_threshold_expression. This may include
Friedelequivalent reflections (i.e. those which are symmetryequivalent under the Laue symmetry but
inequivalent under the crystal class) according to the nature of the structure and the procedures used.
Special characteristics of the reflections included in the _refln_ list should be given in the item
_reflns_special_details.
reflns
Corresponds to the _reflns_number_observed term in the IUCr Core CIF dictionary.
The number of 'observed' reflections in the _refln_ list (not the _diffrn_refln_ list). The
observed reflections satisfy the threshold criterion specified by _reflns_threshold_expression (or the
deprecated item _reflns_observed_criterion). They may include Friedelequivalent reflections according
to the nature of the structure and the procedures used. Special characteristics of the reflections
included in the _refln_ list should be given in the item _reflns_special_details.
reflns
Corresponds to the _reflns_number_total term in the IUCr Core CIF dictionary.
The total number of reflections in the _refln_ list (not the _diffrn_refln_ list). This may include
Friedelequivalent reflections (i.e. those which are symmetryequivalent under the Laue symmetry but
inequivalent under the crystal class) according to the nature of the structure and the procedures used.
Special characteristics of the reflections included in the _refln_ list should be given in the item
_reflns_special_details.
reflns
Corresponds to the _reflns_observed_criterion term in the IUCr Core CIF dictionary.
The criterion used to classify a reflection as 'observed'. This criterion is usually expressed in
terms of a sigma(I) or sigma(F) threshold.
reflns
Corresponds to the _reflns_special_details term in the IUCr Core CIF dictionary.
Description of the properties of the reported reflection list that are not given in other data
items. In particular, this should include information about the averaging (or not) of
symmetryequivalent reflections including Friedel pairs.
reflns
Corresponds to the _reflns_threshold_expression term in the IUCr Core CIF dictionary.
The threshold, usually based on multiples of u(I), u(F^2^) or u(F), that serves to identify
significantly intense reflections, the number of which is given by _reflns_number_gt. These reflections
are used in the calculation of _refine_ls_R_factor_gt.
reflns
Corresponds to the _reflns_class_code term in the IUCr Core CIF dictionary.
The code identifying a certain reflection class.
reflns_class
Corresponds to the _reflns_class_d_res_high term in the IUCr Core CIF dictionary.
For each reflection class, the highest resolution in angstroms for the reflections used in the
refinement. This is the smallest d value.
reflns_class
Corresponds to the _reflns_class_d_res_low term in the IUCr Core CIF dictionary.
For each reflection class, the lowest resolution in angstroms for the reflections used in the
refinement. This is the largest d value.
reflns_class
Corresponds to the _reflns_class_description term in the IUCr Core CIF dictionary.
Description of each reflection class.
reflns_class
Corresponds to the _reflns_class_number_gt term in the IUCr Core CIF dictionary.
For each reflection class, the number of significantly intense reflections (see
_reflns_threshold_expression) in the _refln_ list (not the _diffrn_refln_ list). This may include
Friedel equivalent reflections (i.e. those which are symmetryequivalent under the Laue symmetry but
inequivalent under the crystal class) according to the nature of the structure and the procedures used.
Special characteristics of the reflections included in the _refln_ list should be given in the item
_reflns_special_details.
reflns_class
Corresponds to the _reflns_class_number_total term in the IUCr Core CIF dictionary.
For each reflection class, the total number of reflections in the _refln_ list (not the
_diffrn_refln_ list). This may include Friedelequivalent reflections (i.e. those which are
symmetryequivalent under the Laue symmetry but inequivalent under the crystal class) according to the
nature of the structure and the procedures used. Special characteristics of the reflections included in
the _refln_ list should be given in the item _reflns_special_details.
reflns_class
For each reflection class, the residual factors for all reflections, and for significantly intense
reflections (see _reflns_threshold_expression), included in the refinement. The reflections also satisfy
the resolution limits established by _reflns_class_d_res_high and _reflns_class_d_res_low. This is the
conventional R factor. sum  F(obs)  F(calc)  R =  sum  F(obs)  F(obs) = the
observed structurefactor amplitudes F(calc) = the calculated structurefactor amplitudes and the sum is
taken over the reflections of this class. See also _reflns_class_wR_factor_all definitions.
reflns_class
Corresponds to the _reflns_class_r_factor_all term in the IUCr Core CIF dictionary.
For each reflection class, the residual factors for all reflections, and for significantly intense
reflections (see _reflns_threshold_expression), included in the refinement. The reflections also satisfy
the resolution limits established by _reflns_class_d_res_high and _reflns_class_d_res_low. This is the
conventional R factor. sum  F(obs)  F(calc)  R =  sum  F(obs)  F(obs) = the
observed structurefactor amplitudes F(calc) = the calculated structurefactor amplitudes and the sum is
taken over the reflections of this class. See also _reflns_class_wR_factor_all definitions.
reflns_class
Corresponds to the _reflns_class_r_factor_gt term in the IUCr Core CIF dictionary.
Corresponds to the _reflns_class_r_fsqd_factor term in the IUCr Core CIF dictionary.
For each reflection class, the residual factor R(F^2^) calculated on the squared amplitudes of the
observed and calculated structure factors, for the reflections judged significantly intense (i.e.
satisfying the threshold specified by _reflns_threshold_expression) and included in the refinement. The
reflections also satisfy the resolution limits established by _reflns_class_d_res_high and
_reflns_class_d_res_low. sum  F(obs)^2^  F(calc)^2^  R(Fsqd) =  sum
F(obs)^2^ F(obs)^2^ = squares of the observed structurefactor amplitudes F(calc)^2^ = squares of the
calculated structurefactor amplitudes and the sum is taken over the reflections of this class.
reflns_class
Corresponds to the _reflns_class_r_i_factor term in the IUCr Core CIF dictionary.
For each reflection class, the residual factor R(I) for the reflections judged significantly
intense (i.e. satisfying the threshold specified by _reflns_threshold_expression) and included in the
refinement. This is most often calculated in Rietveld refinements against powder data, where it is
referred to as R~B~ or R~Bragg~. sum  I(obs)  I(calc)  R(I) =  sum  I(obs) 
I(obs) = the net observed intensities I(calc) = the net calculated intensities and the sum is taken over
the reflections of this class.
reflns_class
Corresponds to the _reflns_class_wr_factor_all term in the IUCr Core CIF dictionary.
For each reflection class, the weighted residual factors for all reflections included in the
refinement. The reflections also satisfy the resolution limits established by _reflns_class_d_res_high
and _reflns_class_d_res_low. ( sum w [ Y(obs)  Y(calc) ]^2^ )^1/2^ wR = (
 ) ( sum w Y(obs)^2^ ) Y(obs) = the observed amplitudes specified by
_refine_ls_structure_factor_coef Y(calc) = the calculated amplitudes specified by
_refine_ls_structure_factor_coef w = the leastsquares weights and the sum is taken over the reflections
of this class. See also _reflns_class_R_factor_ definitions.
reflns_class
Corresponds to the _reflns_scale_group_code term in the IUCr Core CIF dictionary.
The code identifying a scale _reflns_scale_meas_. These are linked to the _refln_ list by the
_refln_scale_group_code. These codes need not correspond to those in the _diffrn_scale_ list.
reflns_scale
Scales associated with _reflns_scale_group_code.
reflns_scale
Corresponds to the _reflns_scale_meas_f term in the IUCr Core CIF dictionary.
Scales associated with _reflns_scale_group_code.
reflns_scale
Corresponds to the _reflns_scale_meas_f_squared term in the IUCr Core CIF dictionary.
Scales associated with _reflns_scale_group_code.
reflns_scale
Corresponds to the _reflns_scale_meas_intensity term in the IUCr Core CIF dictionary.
Corresponds to the _reflns_shell_d_res_high term in the IUCr Core CIF dictionary.
The highest resolution in angstroms for the reflections in this shell. This is the smallest d
value.
reflns_shell
Corresponds to the _reflns_shell_d_res_low term in the IUCr Core CIF dictionary.
The lowest resolution in angstroms for the reflections in this shell. This is the largest d value.
reflns_shell
Corresponds to the _reflns_shell_meani_over_sigi_all term in the IUCr Core CIF dictionary.
The ratio of the mean of the intensities of all reflections in this shell to the mean of the
standard uncertainties of the intensities of all reflections in the resolution shell.
reflns_shell
Corresponds to the _reflns_shell_meani_over_sigi_gt term in the IUCr Core CIF dictionary.
The ratio of the mean of the intensities of the significantly intense reflections (see
_reflns_threshold_expression) in this shell to the mean of the standard uncertainties of the intensities
of the significantly intense reflections in the resolution shell.
reflns_shell
Corresponds to the _reflns_shell_meani_over_sigi_obs term in the IUCr Core CIF dictionary.
The ratio of the mean of the intensities of the reflections classified as 'observed' (see
_reflns_observed_criterion) in this shell to the mean of the standard uncertainties of the intensities
of the 'observed' reflections in the resolution shell.
reflns_shell
Corresponds to the _reflns_shell_meani_over_ui_all term in the IUCr Core CIF dictionary.
The ratio of the mean of the intensities of all reflections in this shell to the mean of the
standard uncertainties of the intensities of all reflections in the resolution shell.
reflns_shell
Corresponds to the _reflns_shell_meani_over_ui_gt term in the IUCr Core CIF dictionary.
The ratio of the mean of the intensities of the significantly intense reflections (see
_reflns_threshold_expression) in this shell to the mean of the standard uncertainties of the intensities
of the significantly intense reflections in the resolution shell.
reflns_shell
Corresponds to the _reflns_shell_number_measured_all term in the IUCr Core CIF dictionary.
The total number of reflections measured for this resolution shell.
reflns_shell
Corresponds to the _reflns_shell_number_measured_gt term in the IUCr Core CIF dictionary.
The number of significantly intense reflections (see _reflns_threshold_expression) measured for
this resolution shell.
reflns_shell
Corresponds to the _reflns_shell_number_measured_obs term in the IUCr Core CIF dictionary.
The number of reflections classified as 'observed' (see _reflns_observed_criterion) measured for
this resolution shell.
reflns_shell
Corresponds to the _reflns_shell_number_possible term in the IUCr Core CIF dictionary.
The number of unique reflections it is possible to measure in this reflection shell.
reflns_shell
Corresponds to the _reflns_shell_number_unique_all term in the IUCr Core CIF dictionary.
The total number of measured reflections resulting from merging measured symmetryequivalent
reflections for this resolution shell.
reflns_shell
Corresponds to the _reflns_shell_number_unique_gt term in the IUCr Core CIF dictionary.
The total number of significantly intense reflections (see _reflns_threshold_expression) resulting
from merging measured symmetryequivalent reflections for this resolution shell.
reflns_shell
Corresponds to the _reflns_shell_number_unique_obs term in the IUCr Core CIF dictionary.
The total number of reflections classified as 'observed' (see _reflns_observed_criterion) resulting
from merging measured symmetryequivalent reflections for this resolution shell.
reflns_shell
Corresponds to the _reflns_shell_percent_possible_all term in the IUCr Core CIF dictionary.
The percentage of geometrically possible reflections represented by all reflections measured for
this resolution shell.
reflns_shell
Corresponds to the _reflns_shell_percent_possible_gt term in the IUCr Core CIF dictionary.
The percentage of geometrically possible reflections represented by significantly intense
reflections (see _reflns_threshold_expression) measured for this resolution shell.
reflns_shell
Corresponds to the _reflns_shell_percent_possible_obs term in the IUCr Core CIF dictionary.
The percentage of geometrically possible reflections represented by reflections classified as
'observed' (see _reflns_observed_criterion) measured for this resolution shell.
reflns_shell
Corresponds to the _reflns_shell_rmerge_f_all term in the IUCr Core CIF dictionary.
The value of Rmerge(F) for all reflections in a given shell. sum~i~ ( sum~j~  F~j~  <F>  )
Rmerge(F) =  sum~i~ ( sum~j~ <F> ) F~j~ = the amplitude of the jth
observation of reflection i <F> = the mean of the amplitudes of all observations of reflection i
sum~i~ is taken over all reflections sum~j~ is taken over all observations of each reflection.
reflns_shell
Corresponds to the _reflns_shell_rmerge_f_gt term in the IUCr Core CIF dictionary.
The value of Rmerge(F) for significantly intense reflections (see _reflns_threshold_expression) in
a given shell. sum~i~ ( sum~j~  F~j~  <F>  ) Rmerge(F) = 
sum~i~ ( sum~j~ <F> ) F~j~ = the amplitude of the jth observation of reflection i <F> = the
mean of the amplitudes of all observations of reflection i sum~i~ is taken over all reflections sum~j~
is taken over all observations of each reflection.
reflns_shell
Corresponds to the _reflns_shell_rmerge_f_obs term in the IUCr Core CIF dictionary.
The value of Rmerge(F) for reflections classified as 'observed' (see _reflns_observed_criterion) in
a given shell. sum~i~ ( sum~j~  F~j~  <F>  ) Rmerge(F) = 
sum~i~ ( sum~j~ <F> ) F~j~ = the amplitude of the jth observation of reflection i <F> = the
mean of the amplitudes of all observations of reflection i sum~i~ is taken over all reflections sum~j~
is taken over all observations of each reflection.
reflns_shell
Corresponds to the _reflns_shell_rmerge_i_all term in the IUCr Core CIF dictionary.
The value of Rmerge(I) for all reflections in a given shell. sum~i~ ( sum~j~  I~j~  <I>  )
Rmerge(I) =  sum~i~ ( sum~j~ <I> ) I~j~ = the intensity of the jth
observation of reflection i <I> = the mean of the intensities of all observations of reflection i
sum~i~ is taken over all reflections sum~j~ is taken over all observations of each reflection.
reflns_shell
Corresponds to the _reflns_shell_rmerge_i_gt term in the IUCr Core CIF dictionary.
The value of Rmerge(I) for significantly intense reflections (see _reflns_threshold_expression) in
a given shell. sum~i~ ( sum~j~  I~j~  <I>  ) Rmerge(I) = 
sum~i~ ( sum~j~ <I> ) I~j~ = the intensity of the jth observation of reflection i <I> = the
mean of the intensities of all observations of reflection i sum~i~ is taken over all reflections sum~j~
is taken over all observations of each reflection.
reflns_shell
Corresponds to the _reflns_shell_rmerge_i_obs term in the IUCr Core CIF dictionary.
The value of Rmerge(I) for reflections classified as 'observed' (see _reflns_observed_criterion) in
a given shell. sum~i~ ( sum~j~  I~j~  <I>  ) Rmerge(I) = 
sum~i~ ( sum~j~ <I> ) I~j~ = the intensity of the jth observation of reflection i <I> = the
mean of the intensities of all observations of reflection i sum~i~ is taken over all reflections sum~j~
is taken over all observations of each reflection.
reflns_shell
Corresponds to the _space_group_crystal_system term in the IUCr Core CIF dictionary.
The name of the system of geometric crystal classes of space groups (crystal system) to which the
space group belongs. Note that rhombohedral space groups belong to the trigonal system.
space_group
triclinic
monoclinic
orthorhombic
tetragonal
trigonal
hexagonal
cubic
Corresponds to the _space_group_id term in the IUCr Core CIF dictionary.
This is an identifier needed if _space_group_ items are looped.
space_group
Corresponds to the _space_group_it_number term in the IUCr Core CIF dictionary.
The number as assigned in International Tables for Crystallography Vol. A, specifying the proper
affine class (i.e. the orientationpreserving affine class) of space groups (crystallographic
spacegroup type) to which the space group belongs. This number defines the spacegroup type but not the
coordinate system in which it is expressed.
space_group
Corresponds to the _space_group_name_hm_alt term in the IUCr Core CIF dictionary.
_space_group_name_HM_alt allows any HermannMauguin symbol to be given. The way in which this item
is used is determined by the user and in general is not intended to be interpreted by computer. It may,
for example, be used to give one of the extended HermannMauguin symbols given in Table 4.3.2.1 of
International Tables for Crystallography Vol. A (2002) or a HermannMauguin symbol for a conventional or
unconventional setting. Each component of the spacegroup name is separated by a space or an underscore.
The use of a space is strongly recommended. The underscore is only retained because it was used in older
files. It should not be used in new CIFs. Subscripts should appear without special symbols. Bars should
be given as negative signs before the numbers to which they apply. The commonly used HermannMauguin
symbol determines the space group type uniquely but a given spacegroup type may be described by more
than one HermannMauguin symbol. The space group type is best described using _space_group_IT_number.
The HermannMauguin symbol may contain information on the choice of basis, but not on the choice of
origin. To define the setting uniquely, use _space_group_name_Hall or list the symmetry operations.
space_group
Corresponds to the _space_group_name_hall term in the IUCr Core CIF dictionary.
Spacegroup symbol defined by Hall. Each component of the spacegroup name is separated by a space
or an underscore. The use of a space is strongly recommended. The underscore is only retained because it
was used in older files. It should not be used in new CIFs. _space_group_name_Hall uniquely defines the
space group and its reference to a particular coordinate system. Ref: Hall, S. R. (1981). Acta Cryst.
A37, 517525; erratum (1981), A37, 921. [See also International Tables for Crystallography, Vol. B
(2001), Chapter 1.4, Appendix 1.4.2]
space_group
Corresponds to the _space_group_symop_id term in the IUCr Core CIF dictionary.
An arbitrary identifier that uniquely labels each symmetry operation in the list. In order for the
defaults to work correctly, the identity operation should have _space_group_symop_id or
_symmetry_equiv_pos_site_id set to 1, and _space_group_symop_operation_xyz or _symmetry_equiv_pos_as_xyz
set to x,y,z; i.e. the operation labelled 1 should be the identity operation.
space_group_symop
Corresponds to the _space_group_symop_operation_xyz term in the IUCr Core CIF dictionary.
A parsable string giving one of the symmetry operations of the space group in algebraic form. If W
is a matrix representation of the rotational part of the symmetry operation defined by the positions and
signs of x, y and z, and w is a column of translations defined by fractions, an equivalent position X'
is generated from a given position X by the equation X' = WX + w (Note: X is used to represent
bold_italics_x in International Tables for Crystallography Vol. A, Part 5) When a list of symmetry
operations is given, it must contain a complete set of coordinate representatives which generates all
the operations of the space group by the addition of all primitive translations of the space group. Such
representatives are to be found as the coordinates of the generalequivalent position in International
Tables for Crystallography Vol. A (2002), to which it is necessary to add any centring translations
shown above the generalequivalent position. That is to say, it is necessary to list explicitly all the
symmetry operations required to generate all the atoms in the unit cell defined by the setting used. In
order for the defaults to work correctly, the identity operation should have _space_group_symop_id or
_symmetry_equiv_pos_site_id set to 1, and _space_group_symop_operation_xyz or _symmetry_equiv_pos_as_xyz
set to x,y,z; i.e. the operation labelled 1 should be the identity operation.
space_group_symop
Corresponds to the _space_group_symop_sg_id term in the IUCr Core CIF dictionary.
This must match a particular value of _space_group_id, allowing the symmetry operation to be
identified with a particular space group.
space_group_symop
Corresponds to the _symmetry_cell_setting term in the IUCr Core CIF dictionary.
The cell settings for this spacegroup symmetry.
symmetry
triclinic
monoclinic
orthorhombic
tetragonal
rhombohedral
trigonal
hexagonal
cubic
Corresponds to the _symmetry_int_tables_number term in the IUCr Core CIF dictionary.
Spacegroup number from International Tables for Crystallography Vol. A (2002).
symmetry
Corresponds to the _symmetry_space_group_name_hm term in the IUCr Core CIF dictionary.
HermannMauguin spacegroup symbol. Note that the HermannMauguin symbol does not necessarily
contain complete information about the symmetry and the spacegroup origin. If used, always supply the
FULL symbol from International Tables for Crystallography Vol. A (2002) and indicate the origin and the
setting if it is not implicit. If there is any doubt that the equivalent positions can be uniquely
deduced from this symbol, specify the _symmetry_equiv_pos_as_xyz or *_Hall data items as well. Leave
spaces between symbols referring to different axes.
symmetry
Corresponds to the _symmetry_space_group_name_hall term in the IUCr Core CIF dictionary.
Spacegroup symbol as described by Hall. This symbol gives the spacegroup setting explicitly.
Leave spaces between the separate components of the symbol. Ref: Hall, S. R. (1981). Acta Cryst. A37,
517525; erratum (1981), A37, 921.
symmetry
Corresponds to the _symmetry_equiv_pos_as_xyz term in the IUCr Core CIF dictionary.
Symmetryequivalent position in the 'xyz' representation. Except for the space group P1, these data
will be repeated in a loop. The format of the data item is as per International Tables for
Crystallography Vol. A. (2002). All equivalent positions should be entered, including those for lattice
centring and a centre of symmetry, if present. In order for the defaults to work correctly, the identity
operation should have _space_group_symop_id or _symmetry_equiv_pos_site_id set to 1, and
_space_group_symop_operation_xyz or _symmetry_equiv_pos_as_xyz set to x,y,z; i.e. the operation labelled
1 should be the identity operation.
symmetry_equiv
Corresponds to the _symmetry_equiv_pos_site_id term in the IUCr Core CIF dictionary.
A code identifying each entry in the _symmetry_equiv_pos_as_xyz list. It is normally the sequence
number of the entry in that list, and should be identified with the code 'n' in _geom_*_symmetry_ codes
of the form 'n_klm'. In order for the defaults to work correctly, the identity operation should have
_space_group_symop_id or _symmetry_equiv_pos_site_id set to 1, and _space_group_symop_operation_xyz or
_symmetry_equiv_pos_as_xyz set to x,y,z; i.e. the operation labelled 1 should be the identity operation.
symmetry_equiv
Corresponds to the _valence_param_atom_1 term in the IUCr Core CIF dictionary.
The element symbol of the first atom forming the bond whose bondvalence parameters are given in
this category.
valence_param
Corresponds to the _valence_param_atom_1_valence term in the IUCr Core CIF dictionary.
The valence (formal charge) of the first atom whose bondvalence parameters are given in this
category.
valence_param
Corresponds to the _valence_param_atom_2 term in the IUCr Core CIF dictionary.
The element symbol of the second atom forming the bond whose bondvalence parameters are given in
this category.
valence_param
Corresponds to the _valence_param_atom_2_valence term in the IUCr Core CIF dictionary.
The valence (formal charge) of the second atom whose bondvalence parameters are given in this
category.
valence_param
Corresponds to the _valence_param_b term in the IUCr Core CIF dictionary.
The bondvalence parameter B used in the expression s = exp[(Ro  R)/B] where s is the valence of a
bond of length R.
valence_param
Corresponds to the _valence_param_details term in the IUCr Core CIF dictionary.
Details of or comments on the bondvalence parameters.
valence_param
Corresponds to the _valence_param_id term in the IUCr Core CIF dictionary.
An identifier for the valence parameters of a bond between the given atoms.
valence_param
Corresponds to the _valence_param_ref_id term in the IUCr Core CIF dictionary.
An identifier which links to the reference to the source from which the bondvalence parameters are
taken. A child of _valence_ref_id, which it must match.
valence_param
Corresponds to the _valence_param_ro term in the IUCr Core CIF dictionary.
The bondvalence parameter Ro used in the expression s = exp[(Ro  R)/B] where s is the valence of
a bond of length R.
valence_param
Corresponds to the _valence_ref_id term in the IUCr Core CIF dictionary.
An identifier for items in this category. Parent of _valence_param_ref_id, which must have the same
value.
valence_ref
Corresponds to the _valence_ref_reference term in the IUCr Core CIF dictionary.
Literature reference from which the valence parameters identified by _valence_param_id were taken.
valence_ref