##############################################################################
# #
# Image CIF Dictionary (imgCIF) #
# and Crystallographic Binary File Dictionary (CBF) #
# Extending the Macromolecular CIF Dictionary (mmCIF) #
# #
# Version 1.1.3 #
# of 2001-04-19 #
# #
# Adapted from the #
# imgCIF Workshop, BNL Oct 1997 #
# and #
# Crystallographic Binary File Format Draft Proposal #
# by Andy Hammersley #
# #
##############################################################################
# #
# First DDL 2.1 Version #
# by #
# John Westbrook #
# Nucleic Acid Database #
# Rutgers University #
# #
##############################################################################
# These revisions by: Herbert J. Bernstein, yaya@bernstein-plus-sons.com #
# Incorporating comments by I. David Brown, John Westbrook, Brian McMahon. #
# Bob Sweet, Paul Ellis, Harry Powell, Wilfred Li and others #
##############################################################################
data_cif_img.dic
_dictionary.title cif_img.dic
_dictionary.version 1.1.3
_dictionary.datablock_id cif_img.dic
##############################################################################
# CONTENTS
#
# CATEGORY_GROUP_LIST
#
# category ARRAY_DATA
#
# _array_data.array_id
# _array_data.binary_id
# _array_data.data
#
# category ARRAY_ELEMENT_SIZE
#
# _array_element_size.array_id
# _array_element_size.index
# _array_element_size.size
#
# category ARRAY_INTENSITIES
#
# _array_intensities.array_id
# _array_intensities.binary_id
# _array_intensities.gain
# _array_intensities.gain_esd
# _array_intensities.linearity
# _array_intensities.offset
# _array_intensities.scaling
# _array_intensities.overload
# _array_intensities.undefined_value
#
# category ARRAY_STRUCTURE
#
# _array_structure.byte_order
# _array_structure.compression_type
# _array_structure.encoding_type
# _array_structure.id
#
# category ARRAY_STRUCTURE_LIST
#
# _array_structure_list.axis_set_id
# _array_structure_list.array_id
# _array_structure_list.dimension
# _array_structure_list.direction
# _array_structure_list.index
# _array_structure_list.precedence
#
# category ARRAY_STRUCTURE_LIST_AXIS
#
# _array_structure_list_axis.axis_id
# _array_structure_list_axis.axis_set_id
# _array_structure_list_axis.angle
# _array_structure_list_axis.angle_increment
# _array_structure_list_axis.displacement_increment
# _array_structure_list_axis.angular_pitch
# _array_structure_list_axis.radial_pitch
#
# category AXIS
#
# _axis.depends_on
# _axis.equipment
# _axis.id
# _axis.offset[1]
# _axis.offset[2]
# _axis.offset[3]
# _axis.type
# _axis.vector[1]
# _axis.vector[2]
# _axis.vector[3]
#
# category DIFFRN_DATA_FRAME
#
# _diffrn_data_frame.array_id
# _diffrn_data_frame.binary_id
# _diffrn_data_frame.detector_element_id
# _diffrn_data_frame.id
#
# category DIFFRN_DETECTOR
#
# _diffrn_detector.details
# _diffrn_detector.detector
# _diffrn_detector.diffrn_id
# _diffrn_detector.dtime
# _diffrn_detector.id
# _diffrn_detector.number_of_axes
# _diffrn_detector.type
#
# category DIFFRN_DETECTOR_AXIS
#
# _diffrn_detector_axis.axis_id
# _diffrn_detector_axis.detector_id
#
# category DIFFRN_DETECTOR_ELEMENT
#
# _diffrn_detector_element.center[1]
# _diffrn_detector_element.center[2]
# _diffrn_detector_element.id
# _diffrn_detector_element.detector_id
#
# category DIFFRN_MEASUREMENT
#
# _diffrn_measurement.diffrn_id
# _diffrn_measurement.details
# _diffrn_measurement.device
# _diffrn_measurement.device_details
# _diffrn_measurement.device_type
# _diffrn_measurement.id
# _diffrn_measurement.method
# _diffrn_measurement.number_of_axes
# _diffrn_measurement.specimen_support
#
# category DIFFRN_MEASUREMENT_AXIS
#
# _diffrn_measurement_axis.axis_id
# _diffrn_measurement_axis.measurement_device
# _diffrn_measurement_axis.measurement_id
#
# category DIFFRN_RADIATION
#
# _diffrn_radiation.collimation
# _diffrn_radiation.diffrn_id
# _diffrn_radiation.div_x_source
# _diffrn_radiation.div_y_source
# _diffrn_radiation.div_x_y_source
# _diffrn_radiation.filter_edge'
# _diffrn_radiation.inhomogeneity
# _diffrn_radiation.monochromator
# _diffrn_radiation.polarisn_norm
# _diffrn_radiation.polarisn_ratio
# _diffrn_radiation.polarizn_source_norm
# _diffrn_radiation.polarizn_source_ratio
# _diffrn_radiation.probe
# _diffrn_radiation.type
# _diffrn_radiation.xray_symbol
# _diffrn_radiation.wavelength_id
#
# category DIFFRN_REFLN
#
# _diffrn_refln.frame_id
#
# category DIFFRN_SCAN
#
# _diffrn_scan.id
# _diffrn_scan.date_end
# _diffrn_scan.date_start
# _diffrn_scan.integration_time
# _diffrn_scan.frame_id_start
# _diffrn_scan.frame_id_end
# _diffrn_scan.frames
#
# category DIFFRN_SCAN_AXIS
#
# _diffrn_scan_axis.axis_id
# _diffrn_scan_axis.angle_start
# _diffrn_scan_axis.angle_range
# _diffrn_scan_axis.angle_increment
# _diffrn_scan_axis.angle_rstrt_incr
# _diffrn_scan_axis.displacement_start
# _diffrn_scan_axis.displacement_range
# _diffrn_scan_axis.displacement_increment
# _diffrn_scan_axis.displacement_rstrt_incr
# _diffrn_scan_axis.scan_id
#
# category DIFFRN_SCAN_FRAME
#
# _diffrn_scan_frame.date
# _diffrn_scan_frame.frame_id
# _diffrn_scan_frame.frame_number
# _diffrn_scan_frame.integration_time
# _diffrn_scan_frame.scan_id
#
# category DIFFRN_SCAN_FRAME_AXIS
#
# _diffrn_scan_frame_axis.axis_id
# _diffrn_scan_frame_axis.angle
# _diffrn_scan_frame_axis.angle_increment
# _diffrn_scan_frame_axis.angle_rstrt_incr
# _diffrn_scan_frame_axis.displacement
# _diffrn_scan_frame_axis.displacement_increment
# _diffrn_scan_frame_axis.displacement_rstrt_incr
# _diffrn_scan_frame_axis.frame_id
#
# ITEM_TYPE_LIST
# ITEM_UNITS_LIST
# DICTIONARY_HISTORY
#
##############################################################################
#########################
## CATEGORY_GROUP_LIST ##
#########################
loop_
_category_group_list.id
_category_group_list.parent_id
_category_group_list.description
'inclusive_group' .
; Categories that belong to the dictionary extension.
;
'array_data_group'
'inclusive_group'
; Categories that describe array data.
;
'axis_group'
'inclusive_group'
; Categories that describe axes.
;
'diffrn_group'
'inclusive_group'
; Categories that describe details of the diffraction experiment.
;
##############
# ARRAY_DATA #
##############
save_ARRAY_DATA
_category.description
;
Data items in the ARRAY_DATA category are the containers for
the array data items described in category ARRAY_STRUCTURE.
;
_category.id array_data
_category.mandatory_code no
loop_
_category_key.name '_array_data.array_id'
'_array_data.binary_id'
loop_
_category_group.id 'inclusive_group'
'array_data_group'
loop_
_category_examples.detail
_category_examples.case
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
;
Example 1 -
This example shows two binary data blocks. The first one
was compressed by the CBF_CANONICAL compression algorithm and
presented as hexadecimal data. The first character "H" on the
data lines means hexadecimal. It could have been "O" for octal
or "D" for decimal. The second character on the line shows
the number of bytes in each word (in this case "4"), which then
requires 8 hexadecimal digits per word. The third character
gives the order of octets within a word, in this case "<"
for the ordering 4321 (i.e. "big-endian"). Alternatively the
character ">" could have been used for the ordering 1234
(i.e. "little-endian"). The block has a "message digest"
to check the integrity of the data.
The second block is similar, but uses CBF_PACKED compression
and BASE64 encoding. Note that the size and the digest are
different.
;
;
loop_
_array_data.array_id
_array_data.binary_id
_array_data.data
image_1 1
;
--CIF-BINARY-FORMAT-SECTION--
Content-Type: application/octet-stream;
conversions="x-CBF_CANONICAL"
Content-Transfer-Encoding: X-BASE16
X-Binary-Size: 3927126
X-Binary-ID: 1
Content-MD5: u2sTJEovAHkmkDjPi+gWsg==
# Hexadecimal encoding, byte 0, byte order ...21
#
H4< 0050B810 00000000 00000000 00000000 000F423F 00000000 00000000 ...
....
--CIF-BINARY-FORMAT-SECTION----
;
image_2 2
;
--CIF-BINARY-FORMAT-SECTION--
Content-Type: application/octet-stream;
conversions="x-CBF-PACKED"
Content-Transfer-Encoding: BASE64
X-Binary-Size: 3745758
X-Binary-ID: 1
Content-MD5: 1zsJjWPfol2GYl2V+QSXrw==
ELhQAAAAAAAA...
...
--CIF-BINARY-FORMAT-SECTION----
;
;
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
save_
save__array_data.array_id
_item_description.description
; This item is a pointer to _array_structure.id in the
ARRAY_STRUCTURE category.
;
_item.name '_array_data.array_id'
_item.category_id array_data
_item.mandatory_code yes
_item_type.code code
save_
save__array_data.binary_id
_item_description.description
; This item is an integer identifier which, along with
_array_data.array_id should uniquely identify the
particular block of array data.
If _array_data.binary_id is not explicitly given,
it defaults to 1.
The value of _array_data.binary_id distinguishes
among multiple sets of data with the same array
structure.
If the MIME header of the data array specifies a
value for X-Binary-Id, these values should be equal.
;
loop_
_item.name
_item.category_id
_item.mandatory_code
'_array_data.binary_id' array_data
implicit
'_diffrn_data_frame.binary_id' diffrn_data_frame
implicit
'_array_intensities.binary_id' array_intensities
implicit
loop_
_item_linked.child_name
_item_linked.parent_name
'_diffrn_data_frame.binary_id' '_array_data.binary_id'
'_array_intensities.binary_id' '_array_data.binary_id'
_item_default.value 1
_item_type.code int
loop_
_item_range.maximum
_item_range.minimum
1 1
. 1
save_
save__array_data.data
_item_description.description
; The value of _array_data.data contains the array data
encapsulated in a STAR string.
The representation used is a variant on the
Multipurpose Internet Mail Extensions (MIME) specified
in RFC 2045-2049 by N. Freed et al. The boundary
delimiter used in writing an imgCIF or CBF is
"--CIF-BINARY-FORMAT-SECTION--" (including the
required initial "--").
The Content-Type may be any of the discrete types permitted
in RFC 2045; "application/octet-stream" is recommended.
If an octet stream was compressed, the compression should
be specified by the parameter 'conversions="x-CBF_PACKED"'
or the parameter 'conversions="x-CBF_CANONICAL"'.
The Content-Transfer-Encoding may be "BASE-64",
"Quoted-Printable", "X-BASE-8", "X-BASE-10", or
"X-BASE-16" for an imgCIF or "BINARY" for a CBF. The
octal, decimal and hexadecimal transfer encodings are
for convenience in debugging, and are not recommended
for archiving and data interchange.
In an imgCIF file, the encoded binary data begins after
the empty line terminating the header. In a CBF, the
raw binary data begins after an empty line terminating
the header and after the sequence:
Octet Hex Decimal Purpose
0 0C 12 (ctrl-L) Page break
1 1A 26 (ctrl-Z) Stop listings in MS-DOS
2 04 04 (Ctrl-D) Stop listings in UNIX
3 D5 213 Binary section begins
None of these octets are included in the calculation of
the message size, nor in the calculation of the
message digest.
The X-Binary-Size header specifies the size of the
equivalent binary data in octets. If compression was
used, this size is the size after compression, including
any book-keeping fields. And adjustment is made for
the deprecated binary formats in which 8 bytes of binary
header are used for the compression type. In that case,
the 8 bytes used for the compression type is subtracted
from the size, so that the same size will be reported
if the compression type is supplied in the MIME header.
Use of the MIME header is the recommended way to
supply the compression type. In general, no portion of
the binary header is included in the calculation of the size.
The X-Binary-Element-Type header specifies the type of
binary data in the octets, using the same descriptive
phrases as in _array_structure.encoding_type. The default
value is "unsigned 32-bit integer".
An MD5 message digest may, optionally, be used. The "RSA Data
Security, Inc. MD5 Message-Digest Algorithm" should be used.
No portion of the header is included in the calculation of the
message digest.
If the Transfer Encoding is "X-BASE-8", "X-BASE-10", or
"X-BASE-16", the data is presented as octal, decimal or
hexadecimal data organized into lines or words. Each word
is created by composing octets of data in fixed groups of
2, 3, 4, 6 or 8 octets, either in the order ...4321 ("big-
endian") or 1234... (little-endian). If there are fewer
than the specified number of octets to fill the last word,
then the missing octets are presented as "==" for each
missing octet. Exactly two equal signs are used for each
missing octet even for octal and decimal encoding.
The format of lines is:
rnd xxxxxx xxxxxx xxxxxx
where r is "H", "O", or "D" for hexadecimal, octal or
decimal, n is the number of octets per word. and d is "<"
for ">" for the "...4321" and "1234..." octet orderings
respectively. The "==" padding for the last word should
be on the appropriate side to correspond to the missing
octets, e.g.
H4< FFFFFFFF FFFFFFFF 07FFFFFF ====0000
or
H3> FF0700 00====
For these hex, octal and decimal formats, only, comments
beginning with "#" are permitted to improve readability.
BASE64 encoding follows MIME conventions. Octets are
in groups of three, c1, c2, c3. The resulting 24 bits
are broken into four 6-bit quantities, starting with
the high-order six bits (c1 >> 2) of the first octet, then
the low-order two bits of the first octet followed by the
high-order 4 bits of the second octet ((c1 & 3)<<4 | (c2>>4)),
then the bottom 4 bits of the second octet followed by the
high order two bits of the last octet ((c2 & 15)<<2 | (c3>>6)),
then the bottom six bits of the last octet (c3 & 63). Each
of these four quantities is translated into an ASCII character
using the mapping:
1 2 3 4 5 6
0123456789012345678901234567890123456789012345678901234567890123
| | | | | | |
ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/
With short groups of octets padded on the right with one "="
if c3 is missing, and with "==" if both c2 and c3 are missing.
QUOTED-PRINTABLE encoding also follows MIME conventions, copying
octets without translation if their ASCII values are 32..38,
42, 48..57, 59..60, 62, 64..126 and the octet is not a ";"
in column 1. All other characters are translated to =nn, where
nn is the hexadecimal encoding of the octet. All lines are
"wrapped" with a terminating "=" (i.e. the MIME conventions
for an implicit line terminator are never used).
;
_item.name '_array_data.data'
_item.category_id array_data
_item.mandatory_code yes
_item_type.code binary
save_
######################
# ARRAY_ELEMENT_SIZE #
######################
save_ARRAY_ELEMENT_SIZE
_category.description
;
Data items in the ARRAY_ELEMENT_SIZE category record the physical
size of array elements along each array dimension.
;
_category.id array_element_size
_category.mandatory_code no
loop_
_category_key.name '_array_element_size.array_id'
'_array_element_size.index'
loop_
_category_group.id 'inclusive_group'
'array_data_group'
loop_
_category_examples.detail
_category_examples.case
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
;
Example 1 - A regular 2D array with a uniform element dimension
of 1220 nanometres.
;
;
loop_
_array_element_size.array_id
_array_element_size.index
_array_element_size.size
image_1 1 1.22e-6
image_1 2 1.22e-6
;
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
save_
save__array_element_size.array_id
_item_description.description
;
This item is a pointer to _array_structure.id in the
ATOM_STRUCTURE category.
;
_item.name '_array_element_size.array_id'
_item.category_id array_element_size
_item.mandatory_code yes
_item_type.code code
save_
save__array_element_size.index
_item_description.description
;
This item is a pointer to _array_structure_list.index in the
ATOM_STRUCTURE_LIST category.
;
_item.name '_array_element_size.index'
_item.category_id array_element_size
_item.mandatory_code yes
_item_type.code code
save_
save__array_element_size.size
_item_description.description
;
The size in metres of an image element in this
dimension. This supposes that the elements are arranged
on a regular grid.
;
_item.name '_array_element_size.size'
_item.category_id array_element_size
_item.mandatory_code yes
_item_type.code float
_item_units.code 'metres'
loop_
_item_range.maximum
_item_range.minimum
. 0.0
save_
#####################
# ARRAY_INTENSITIES #
#####################
save_ARRAY_INTENSITIES
_category.description
;
Data items in the ARRAY_INTENSITIES category record the
information required to recover the intensity data from
the set of data values stored in the ARRAY_DATA category.
The actual detector may have a complex relationship
between the raw intensity values and the number of
incident photons. In most cases, the number stored
in the final array will have a simple linear relationship
to the actual number of incident photons, given by
'_array_intensities.gain'. If raw, uncorrected values
are presented (e.g for calibration experiments), the
value of '_array_intensities.linearity' will be 'raw'
and '_array_intensities.gain' will not be used.
;
_category.id array_intensities
_category.mandatory_code no
loop_
_category_key.name '_array_intensities.array_id'
'_array_intensities.binary_id'
loop_
_category_group.id 'inclusive_group'
'array_data_group'
loop_
_category_examples.detail
_category_examples.case
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
;
Example 1
;
;
loop_
_array_intensities.array_id
_array_intensities.linearity
_array_intensities.gain
_array_intensities.overload
_array_intensities.undefined_value
image_1 linear 1.2 655535 0
;
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
save_
save__array_intensities.array_id
_item_description.description
;
This item is a pointer to _array_structure.id in the
ATOM_STRUCTURE category.
;
_item.name '_array_intensities.array_id'
_item.category_id array_intensities
_item.mandatory_code yes
_item_type.code code
save_
save__array_intensities.binary_id
_item_description.description
; This item is a pointer to _array_data.binary_id in the
ARRAY_STRUCTURE category.
;
_item.name '_array_intensities.binary_id'
_item.category_id array_intensities
_item.mandatory_code implicit
_item_type.code int
save_
save__array_intensities.gain
_item_description.description
;
Detector "gain". The factor by which linearized
intensity count values should be divided to produce
true photon counts.
;
_item.name '_array_intensities.gain'
_item.category_id array_intensities
_item.mandatory_code yes
_item_type.code float
loop_
_item_range.maximum
_item_range.minimum
. 0.0
_item_units.code 'counts_per_photon'
loop_
_item_related.related_name
_item_related.function_code '_array_intensities.gain_esd'
'associated_value'
save_
save__array_intensities.gain_esd
_item_description.description
;
The estimated standard deviation in detector "gain".
;
_item.name '_array_intensities.gain_esd'
_item.category_id array_intensities
_item.mandatory_code yes
_item_type.code float
_item_units.code 'counts_per_photon'
loop_
_item_related.related_name
_item_related.function_code '_array_intensities.gain'
'associated_esd'
save_
save__array_intensities.linearity
_item_description.description
;
The intensity linearity scaling used from raw intensity
to the stored element value:
'linear' is obvious
'offset' means that the value defined by
'_array_intensities.offset' should be added to each
element value.
'scaling' means that the value defined by
'_array_intensities.scaling' should be multiplied with each
element value.
'scaling_offset' is the combination of the two previous cases,
with the scale factor applied before the offset value.
'sqrt_scaled' means that the square root of raw
intensities multiplied by '_array_intensities.scaling' is
calculated and stored, perhaps rounded to the nearest
integer. Thus, linearization involves dividing the stored
values by '_array_intensities.scaling' and squaring the
result.
'logarithmic_scaled' means that the logarithm based 10 of
raw intensities multiplied by '_array_intensities.scaling'
is calculated and stored, perhaps rounded to the nearest
integer. Thus, linearization involves dividing the stored
values by '_array_intensities.scaling' and calculating 10
to the power of this number.
'raw' means that the data is the raw is a set of raw values
straight from the detector.
;
_item.name '_array_intensities.linearity'
_item.category_id array_intensities
_item.mandatory_code yes
_item_type.code code
loop_
_item_enumeration.value
_item_enumeration.detail
'linear' .
'offset'
;
The value defined by '_array_intensities.offset' should
be added to each element value.
;
'scaling'
;
The value defined by '_array_intensities.scaling' should be
multiplied with each element value.
;
'scaling_offset'
;
The combination of the scaling and offset
with the scale factor applied before the offset value.
;
'sqrt_scaled'
;
The square root of raw intensities multiplied by
'_array_intensities.scaling' is calculated and stored,
perhaps rounded to the nearest integer. Thus,
linearization involves dividing the stored
values by '_array_intensities.scaling' and squaring the
result.
;
'logarithmic_scaled'
;
The logarithm based 10 of raw intensities multiplied by
'_array_intensities.scaling' is calculated and stored,
perhaps rounded to the nearest integer. Thus,
linearization involves dividing the stored values by
'_array_intensities.scaling' and calculating 10 to the
power of this number.
;
'raw'
;
The array consists of raw values to which no corrections have
been applied. While the handling of the data is similar to
that given for 'linear' data with no offset, the meaning of
the data differs in that the number of incident photons is
not necessarily linearly related to the number of counts
reported. This value is intended for use either in
calibration experiments or to allow for handling more
complex data fitting algorithms than are allowed for by
this data item.
;
save_
save__array_intensities.offset
_item_description.description
;
Offset value to add to array element values in the manner
described by item _array_intensities.linearity.
;
_item.name '_array_intensities.offset'
_item.category_id array_intensities
_item.mandatory_code no
_item_type.code float
save_
save__array_intensities.scaling
_item_description.description
;
Multiplicative scaling value to be applied to array data
in the manner described by item _array_intensities.linearity.
;
_item.name '_array_intensities.scaling'
_item.category_id array_intensities
_item.mandatory_code no
_item_type.code float
save_
save__array_intensities.overload
_item_description.description
;
The saturation intensity level for this data array.
;
_item.name '_array_intensities.overload'
_item.category_id array_intensities
_item.mandatory_code no
_item_type.code float
_item_units.code 'counts'
save_
save__array_intensities.undefined_value
_item_description.description
;
A value to be substituted for undefined values in
the data array.
;
_item.name '_array_intensities.undefined_value'
_item.category_id array_intensities
_item.mandatory_code no
_item_type.code float
save_
###################
# ARRAY_STRUCTURE #
###################
save_ARRAY_STRUCTURE
_category.description
;
Data items in the ARRAY_STRUCTURE category record the organization and
encoding of array data which may be stored in the ARRAY_DATA category.
;
_category.id array_structure
_category.mandatory_code no
_category_key.name '_array_structure.id'
loop_
_category_group.id 'inclusive_group'
'array_data_group'
loop_
_category_examples.detail
_category_examples.case
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
;
Example 1 -
;
;
loop_
_array_structure.id
_array_structure.encoding_type
_array_structure.compression_type
_array_structure.byte_order
image_1 "unsigned 16-bit integer" none little_endian
;
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
save_
save__array_structure.byte_order
_item_description.description
;
The order of bytes for integer values which require more
than 1-byte.
(IBM-PC's and compatibles, and Dec-Vaxes use low-byte-first
ordered integers, whereas Hewlett Packard 700
series, Sun-4 and Silicon Graphics use high-byte-first
ordered integers. Dec-Alphas can produce/use either
depending on a compiler switch.)
;
_item.name '_array_structure.byte_order'
_item.category_id array_structure
_item.mandatory_code yes
_item_type.code code
loop_
_item_enumeration.value
_item_enumeration.detail
'big_endian'
;
The first byte in the byte stream of the bytes which make up an
integer value is the most significant byte of an integer.
;
'little_endian'
;
The last byte in the byte stream of the bytes which make up an
integer value is the most significant byte of an integer.
;
save_
save__array_structure.compression_type
_item_description.description
;
Type of data compression method used to compress the array
data.
;
_item.name '_array_structure.compression_type'
_item.category_id array_structure
_item.mandatory_code no
_item_type.code code
_item_default.value 'none'
loop_
_item_enumeration.value
_item_enumeration.detail
'none'
;
Data are stored in normal format as defined by
'_array_structure.encoding_type' and
'_array_structure.byte_order'.
;
'byte_offsets'
;
Using the compression scheme defined in CBF definition
Section 5.0.
;
'packed'
;
Using the 'packed' compression scheme, a CCP4-style packing
(CBFlib section 3.3.2)
;
'canonical'
;
Using the 'canonical' compression scheme (CBFlib section
3.3.1)
;
save_
save__array_structure.encoding_type
_item_description.description
;
Data encoding of a single element of array data.
In several cases, the IEEE format is referenced.
See "IEEE Standard for Binary Floating-Point Arithmetic",
ANSI/IEEE Std 754-1985, the Institute of Electrical and
Electronics Engineers, Inc., NY 1985.
;
_item.name '_array_structure.encoding_type'
_item.category_id array_structure
_item.mandatory_code yes
_item_type.code uline
loop_
_item_enumeration.value
'unsigned 8-bit integer'
'signed 8-bit integer'
'unsigned 16-bit integer'
'signed 16-bit_integer'
'unsigned 32-bit integer'
'signed 32-bit integer'
'signed 32-bit real IEEE'
'signed 64-bit real IEEE'
'signed 32-bit complex IEEE'
save_
save__array_structure.id
_item_description.description
; The value of _array_structure.id must uniquely identify
each item of array data.
;
loop_
_item.name
_item.category_id
_item.mandatory_code
'_array_structure.id' array_structure yes
'_array_data.array_id' array_data yes
'_array_structure_list.array_id' array_structure_list yes
'_array_intensities.array_id' array_intensities yes
'_diffrn_data_frame.array_id' diffrn_data_frame yes
_item_type.code code
loop_
_item_linked.child_name
_item_linked.parent_name
'_array_data.array_id' '_array_structure.id'
'_array_structure_list.array_id' '_array_structure.id'
'_array_intensities.array_id' '_array_structure.id'
'_diffrn_data_frame.array_id' '_array_structure.id'
save_
########################
# ARRAY_STRUCTURE_LIST #
########################
save_ARRAY_STRUCTURE_LIST
_category.description
;
Data items in the ARRAY_STRUCTURE_LIST category record the size
and organization of each array dimension.
The relationship to physical axes may be given.
;
_category.id array_structure_list
_category.mandatory_code no
loop_
_category_key.name '_array_structure_list.array_id'
'_array_structure_list.index'
loop_
_category_group.id 'inclusive_group'
'array_data_group'
loop_
_category_examples.detail
_category_examples.case
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
;
Example 1 - An image array of 1300 x 1200 elements. The raster
order of the image is left-to-right (increasing) in
first dimension and bottom-to-top (decreasing) in
the second dimension.
;
;
loop_
_array_structure_list.array_id
_array_structure_list.index
_array_structure_list.dimension
_array_structure_list.precedence
_array_structure_list.direction
_array_structure_list.axis_set_id
image_1 1 1300 1 increasing ELEMENT_X
image_1 2 1200 2 decreasing ELEMENY_Y
;
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
save_
save__array_structure_list.array_id
_item_description.description
;
This item is a pointer to _array_structure.id in the
ARRAY_STRUCTURE category.
;
_item.name '_array_structure_list.array_id'
_item.category_id array_structure_list
_item.mandatory_code yes
_item_type.code code
save_
save__array_structure_list.axis_set_id
_item_description.description
; This is a descriptor for the physical axis or set of axes
corresponding to an array index.
This data item is related to the axes of the detector
itself given in DIFFRN_DETECTOR_AXIS, but usually differ
in that the axes in this category are the axes of the
coordinate system of reported data points, while the axes in
DIFFRN_DETECTOR_AXIS are the physical axes
of the detector describing the "poise" of the detector as an
overall physical object.
If there is only one axis in the set, the identifier of
that axis should be used as the identifier of the set.
;
loop_
_item.name
_item.category_id
_item.mandatory_code
'_array_structure_list.axis_set_id'
array_structure_list yes
'_array_structure_list_axis.axis_set_id'
array_structure_list_axis implicit
_item_type.code code
loop_
_item_linked.child_name
_item_linked.parent_name
'_array_structure_list_axis.axis_set_id'
'_array_structure_list.axis_set_id'
save_
save__array_structure_list.dimension
_item_description.description
;
The number of elements stored in the array structure in this
dimension.
;
_item.name '_array_structure_list.dimension'
_item.category_id array_structure_list
_item.mandatory_code yes
_item_type.code int
loop_
_item_range.maximum
_item_range.minimum
1 1
. 1
save_
save__array_structure_list.direction
_item_description.description
;
Identifies the direction in which this array index changes.
;
_item.name '_array_structure_list.direction'
_item.category_id array_structure_list
_item.mandatory_code yes
_item_type.code int
loop_
_item_enumeration.value
_item_enumeration.detail
'increasing'
;
Indicates the index changes from 1 to the maximum dimension.
;
'decreasing'
;
Indicates the index changes from the maximum dimension to 1.
;
save_
save__array_structure_list.index
_item_description.description
;
Identifies the one-based index of the row or column in the
array structure.
;
loop_
_item.name
_item.category_id
_item.mandatory_code
'_array_structure_list.index' array_structure_list yes
'_array_structure_list.precedence' array_structure_list yes
'_array_element_size.index' array_element_size yes
_item_type.code int
loop_
_item_linked.child_name
_item_linked.parent_name
'_array_element_size.index' '_array_structure_list.index'
loop_
_item_range.maximum
_item_range.minimum
1 1
. 1
save_
save__array_structure_list.precedence
_item_description.description
;
Identifies the rank order in which this array index changes
with respect to other array indices. The precedence of 1
indicates the index which changes fastest.
;
_item.name '_array_structure_list.precedence'
_item.category_id array_structure_list
_item.mandatory_code yes
_item_type.code int
loop_
_item_range.maximum
_item_range.minimum
1 1
. 1
save_
#############################
# ARRAY_STRUCTURE_LIST_AXIS #
#############################
save_ARRAY_STRUCTURE_LIST_AXIS
_category.description
;
Data items in the ARRAY_STRUCTURE_LIST_AXIS category describes
the physical settings of sets axes for the centres of pixels that
correspond to data points described in the
ARRAY_STRUCTURE_LIST category.
In the simplest cases, the physical increments of a single axis correspond
to the increments of a single array index. More complex organizations,
e.g. spiral scans, may require coupled motions along multiple axes.
Note that a spiral scan uses two coupled axis, one for the angular
direction, one for the radial direction. This differs from a
cylindrical scan for which the two axes are not coupled into one set.
;
_category.id array_structure_list_axis
_category.mandatory_code no
loop_
_category_key.name
'_array_structure_list_axis.axis_set_id'
'_array_structure_list_axis.axis_id'
loop_
_category_group.id 'inclusive_group'
'array_data_group'
save_
save__array_structure_list_axis.axis_id
_item_description.description
;
The value of this data item is the identifier of one of
the axes for the set of axes for which settings are being
specified.
Multiple axes may be specified for the same value of
'_array_structure_list_axis.axis_set_id'
This item is a pointer to _axis.id in the
AXIS category.
;
_item.name '_array_structure_list_axis.axis_id'
_item.category_id array_structure_list_axis
_item.mandatory_code yes
save_
save__array_structure_list_axis.axis_set_id
_item_description.description
;
The value of this data item is the identifier of the
set of axes for which axis settings are being specified.
Multiple axes may be specified for the same value of
_array_structure_list_axis.axis_set_id .
This item is a pointer to _array_structure_list.axis_set_id
in the ARRAY_STRUCTURE_LIST category.
If this item is not specified, it defaults to the corresponding
axis identifier.
;
_item.name '_array_structure_list_axis.axis_set_id'
_item.category_id array_structure_list_axis
_item.mandatory_code implicit
save_
save__array_structure_list_axis.angle
_item_description.description
;
The setting of the specified axis in degrees for the first
data point of the array index with the corresponding value
of '_array_structure_list.axis_set_id'. If the index is
specified as 'increasing' this will be the center of the
pixel with index value 1. If the index is specified as
'decreasing' this will be the center of the pixel with
maximum index value.
;
_item.name '_array_structure_list_axis.angle'
_item.category_id array_structure_list_axis
_item.mandatory_code no
_item_default.value 0.0
_item_type.code float
_item_units.code 'degrees'
save_
save__array_structure_list_axis.angle_increment
_item_description.description
;
The pixel-center-to-pixel-center increment in the angular
setting of the specified axis in degrees. This is not
meaningful in the case of 'constant velocity' spiral scans
and should not be specified in that case.
See '_array_structure_list_axis.angular_pitch'.
;
_item.name '_array_structure_list_axis.angle_increment'
_item.category_id array_structure_list_axis
_item.mandatory_code no
_item_default.value 0.0
_item_type.code float
_item_units.code 'degrees'
save_
save__array_structure_list_axis.displacement
_item_description.description
;
The setting of the specified axis in millimetres for the first
data point of the array index with the corresponding value
of '_array_structure_list.axis_set_id'. If the index is
specified as 'increasing' this will be the center of the
pixel with index value 1. If the index is specified as
'decreasing' this will be the center of the pixel with
maximum index value.
;
_item.name '_array_structure_list_axis.displacement'
_item.category_id array_structure_list_axis
_item.mandatory_code no
_item_default.value 0.0
_item_type.code float
_item_units.code 'millimetres'
save_
save__array_structure_list_axis.displacement_increment
_item_description.description
;
The pixel-center-to-pixel-center increment for the displacement
setting of the specified axis in millimetres.
;
_item.name
'_array_structure_list_axis.displacement_increment'
_item.category_id array_structure_list_axis
_item.mandatory_code no
_item_default.value 0.0
_item_type.code float
_item_units.code 'millimetres'
save_
save__array_structure_list_axis.angular_pitch
_item_description.description
;
The pixel-center-to-pixel-center distance for a one step
change in the setting of the specified axis in millimetres.
This is meaningful only for 'constant velocity' spiral scans,
or for uncoupled angular scans at a constant radius
(cylindrical scan) and should not be specified for cases
in which the angle between pixels, rather than the distance
between pixels is uniform.
See '_array_structure_list_axis.angle_increment'.
;
_item.name '_array_structure_list_axis.angular_pitch'
_item.category_id array_structure_list_axis
_item.mandatory_code no
_item_default.value 0.0
_item_type.code float
_item_units.code 'millimetres'
save_
save__array_structure_list_axis.radial_pitch
_item_description.description
;
The radial distance from one "cylinder" of pixels to the
next in millimetres. If the scan is a 'constant velocity'
scan with differing angular displacements between pixels,
the value of this item may differ significantly from the
value of '_array_structure_list_axis.displacement_increment'.
;
_item.name '_array_structure_list_axis.radial_pitch'
_item.category_id array_structure_list_axis
_item.mandatory_code no
_item_default.value 0.0
_item_type.code float
_item_units.code 'millimetres'
save_
########
# AXIS #
########
save_AXIS
_category.description
;
Data items in the AXIS category record the information required
to describe the various goniometer, detector, source and other
axes needed to specify a data collection. The location of each
axis is specified by two vectors: the axis itself, given as a unit
vector, and an offset to the base of the unit vector. These vectors
are referenced to a right-handed laboratory coordinate system with
its origin in the sample or specimen:
| Y (to complete right-handed system)
|
|
|
|
|
|________________X
/ principal goniometer axis
/
/
/
/
/Z (to source)
Axis 1 (X): The X-axis is aligned to the mechanical axis pointing from
the sample or specimen along the principal axis of the goniometer.
Axis 2 (Y): The Y-axis completes an orthogonal right-handed system
defined by the X-axis and the Z-axis (see below).
Axis 3 (Z): The Z-axis is derived from the source axis which goes from
the sample to the source. The Z-axis is the component of the source axis
in the direction of the source orthogonal to the X-axis in the plane
defined by the X-axis and the source axis.
These axes are based on the goniometer, not on the orientation of the
detector, gravity, etc. The vectors necessary to specify all other
axes are given by sets of three components in the order (X, Y, Z).
If the axis involved is a rotation axis, it is right handed, i.e. as
one views the object to be rotated from the origin (the tail) of the
unit vector, the rotation is clockwise. If a translation axis is
specified, the direction of the unit vector specifies the sense of
positive translation.
Note: This choice of coordinate system is similar to, but significantly
different from the choice in MOSFLM (Andrew G.W. Leslie, Harry Powell,
MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH,UK
http://www.dl.ac.uk/CCP/CCP4/dist/x-windows/Mosflm/). In MOSFLM,
X is along the X-ray beam (our Z axis) and Z is along the rotation axis.
All rotations are given in degrees and all translations are given in mm.
Axes may be dependent on one another. The X-axis is the only goniometer
axis the direction of which is strictly connected to the hardware. All
other axes are specified by the positions they would assume when the
axes upon which they depend are at their zero points.
When specifying detector axes, the axis is given to the beam center.
The location of the beam center on the detector should be given in the
DIFFRN_DETECTOR category in distortion-corrected mm from the (0,0) corner
of the detector.
It should be noted that many different origins arise in the definition
of an experiment. In particular, as noted above, we need to specify the
location of the beam center on the detector in terms of the origin of the
detector, which is, of course, not coincident with the center of the
sample.
;
_category.id axis
_category.mandatory_code no
loop_
_category_key.name '_axis.id'
'_axis.equipment'
loop_
_category_group.id 'inclusive_group'
'axis_group'
'diffrn_group'
loop_
_category_examples.detail
_category_examples.case
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
;
Example 1 -
This example shows the axis specification of the axes of a kappa
geometry goniometer (See "X-Ray Structure Determination, A Practical
Guide", 2nd ed. by G. H. Stout, L. H. Jensen, Wiley Interscience,
1989, 453 pp, p 134.).
There are three axes specified, and no offsets. The outermost axis,
omega, is pointed along the X-axis. The next innermost axis, kappa,
is at a 50 degree angle to the X-axis, pointed away from the source.
The innermost axis, phi, aligns with the X-axis when omega and
phi are at their zero-points. If T-omega, T-kappa and T-phi
are the transformation matrices derived from the axis settings,
the complete transformation would be:
x' = (T-omega) (T-kappa) (T-phi) x
;
;
loop_
_axis.id
_axis.type
_axis.equipment
_axis.depends_on
_axis.vector[1] _axis.vector[2] _axis.vector[3]
omega rotation goniometer . 1 0 0
kappa rotation goniometer omega -.64279 0 -.76604
phi rotation goniometer kappa 1 0 0
;
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
;
Example 2 -
This example show the axis specification of the axes of a
detector, source and gravity. We have juggled the order as a
reminder that the ordering of presentation of tokens is not
significant. We have taken the center of rotation of the detector
to be 68 millimetres in the direction away from the source.
;
;
loop_
_axis.id
_axis.type
_axis.equipment
_axis.depends_on
_axis.vector[1] _axis.vector[2] _axis.vector[3]
_axis.offset[1] _axis.offset[2] _axis.offset[3]
source . source . 0 0 1 . . .
gravity . gravity . 0 -1 0 . . .
tranz translation detector rotz 0 0 1 0 0 -68
twotheta rotation detector . 1 0 0 . . .
roty rotation detector twotheta 0 1 0 0 0 -68
rotz rotation detector roty 0 0 1 0 0 -68
;
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
save_
save__axis.depends_on
_item_description.description
; The value of _axis.type specifies the next outermost
axis upon which this axis depends.
This item is a pointer to axis.id in the same category.
;
_item.name '_axis.depends_on'
_item.category_id axis
_item.mandatory_code no
save_
save__axis.equipment
_item_description.description
; The value of _axis.type specifies the type of equipment
using the axis: goniometer, detector, gravity, source
or general
;
_item.name '_axis.equipment'
_item.category_id axis
_item.mandatory_code no
_item_type.code ucode
_item_default.value general
loop_
_item_enumeration.value
_item_enumeration.detail goniometer
'equipment used to orient or position samples'
detector
'equipment used to detect reflections'
general
'equipment used for general purposes'
gravity
'axis specifying the downward direction'
source
'axis specifying the direction sample to source'
save_
save__axis.offset[1]
_item_description.description
; The [1] element of the 3-element vector used to specify
the offset to the base of a rotation or translation axis.
The vector is specified in millimetres
;
_item.name '_axis.offset[1]'
_item.category_id axis
_item.mandatory_code no
_item_default.value 0.0
_item_sub_category.id vector
_item_type.code float
_item_units.code millimetres
save_
save__axis.offset[2]
_item_description.description
; The [2] element of the 3-element vector used to specify
the offset to the base of a rotation or translation axis.
The vector is specified in millimetres
;
_item.name '_axis.offset[2]'
_item.category_id axis
_item.mandatory_code no
_item_default.value 0.0
_item_sub_category.id vector
_item_type.code float
_item_units.code millimetres
save_
save__axis.offset[3]
_item_description.description
; The [3] element of the 3-element vector used to specify
the offset to the base of a rotation or translation axis.
The vector is specified in millimetres
;
_item.name '_axis.offset[3]'
_item.category_id axis
_item.mandatory_code no
_item_default.value 0.0
_item_sub_category.id vector
_item_type.code float
_item_units.code millimetres
save_
save__axis.id
_item_description.description
; The value of _axis.id must uniquely identify
each axis relevant to the experiment. Note that multiple
pieces of equipment may share the same axis (e.g. a twotheta
arm), so that the category key for AXIS also includes the
equipment.
;
loop_
_item.name
_item.category_id
_item.mandatory_code
'_axis.id' axis yes
'_array_structure_list_axis.axis_id'
array_structure_list_axis
yes
'_diffrn_detector_axis.axis_id' diffrn_detector_axis yes
'_diffrn_measurement_axis.axis_id' diffrn_measurement_axis yes
'_diffrn_scan_axis.axis_id' diffrn_scan_axis yes
'_diffrn_scan_frame_axis.axis_id' diffrn_scan_frame_axis yes
_item_type.code code
loop_
_item_linked.child_name
_item_linked.parent_name
'_axis.depends_on' '_axis.id'
'_array_structure_list_axis.axis_id' '_axis.id'
'_diffrn_detector_axis.axis_id' '_axis.id'
'_diffrn_measurement_axis.axis_id' '_axis.id'
'_diffrn_scan_axis.axis_id' '_axis.id'
'_diffrn_scan_frame_axis.axis_id' '_axis.id'
save_
save__axis.type
_item_description.description
; The value of _axis.type specifies the type of
axis: rotation, translation (or general when the type is
not relevant, as for gravity)
;
_item.name '_axis.type'
_item.category_id axis
_item.mandatory_code no
_item_type.code ucode
_item_default.value general
loop_
_item_enumeration.value
_item_enumeration.detail rotation
'right-handed axis of rotation'
translation
'translation in the direction of the axis'
general
'axis for which the type is not relevant'
save_
save__axis.vector[1]
_item_description.description
; The [1] element of the 3-element vector used to specify
the direction of a rotation or translation axis.
The vector should be normalized to be a unit vector, and
is dimensionless.
;
_item.name '_axis.vector[1]'
_item.category_id axis
_item.mandatory_code no
_item_default.value 0.0
_item_sub_category.id vector
_item_type.code float
save_
save__axis.vector[2]
_item_description.description
; The [2] element of the 3-element vector used to specify
the direction of a rotation or translation axis.
The vector should be normalized to be a unit vector, and
is dimensionless.
;
_item.name '_axis.vector[2]'
_item.category_id axis
_item.mandatory_code no
_item_default.value 0.0
_item_sub_category.id vector
_item_type.code float
save_
save__axis.vector[3]
_item_description.description
; The [3] element of the 3-element vector used to specify
the direction of a rotation or translation axis.
The vector should be normalized to be a unit vector, and
is dimensionless.
;
_item.name '_axis.vector[3]'
_item.category_id axis
_item.mandatory_code no
_item_default.value 0.0
_item_sub_category.id vector
_item_type.code float
save_
#####################
# DIFFRN_DATA_FRAME #
#####################
save_DIFFRN_DATA_FRAME
_category.description
;
Data items in the DIFFRN_DATA_FRAME category record
the details about each frame of data.
The items in this category were previously in a
DIFFRN_FRAME_DATA category, which is now deprecated.
The items from the old category are provided
as aliases, but should not be used for new work.
;
_category.id diffrn_data_frame
_category.mandatory_code no
loop_
_category_key.name '_diffrn_data_frame.id'
'_diffrn_data_frame.detector_element_id'
loop_
_category_group.id 'inclusive_group'
'array_data_group'
loop_
_category_examples.detail
_category_examples.case
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
;
Example 1 - A frame containing data from 4 frame elements.
Each frame element has a common array configuration
'array_1' described in ARRAY_STRUCTURE and related
categories. The data for each detector element is
stored in four groups of binary data in the
ARRAY_DATA category, linked by the array_id and
binary_id
;
;
loop_
_diffrn_data_frame.id
_diffrn_data_frame.detector_element_id
_diffrn_data_frame.array_id
_diffrn_data_frame.binary_id
frame_1 d1_ccd_1 array_1 1
frame_1 d1_ccd_2 array_1 2
frame_1 d1_ccd_3 array_1 3
frame_1 d1_ccd_4 array_1 4
;
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
save_
save__diffrn_data_frame.array_id
_item_description.description
;
This item is a pointer to _array_structure.id in the
ARRAY_STRUCTURE category.
;
_item.name '_diffrn_data_frame.array_id'
_item.category_id diffrn_data_frame
_item.mandatory_code yes
_item_aliases.alias_name '_diffrn_frame_data.array_id'
_item_aliases.dictionary cif_img.dic
_item_aliases.version 1.0.00
_item_type.code code
save_
save__diffrn_data_frame.binary_id
_item_description.description
; This item is a pointer to _array_data.binary_id in the
ARRAY_DATA category.
;
_item.name '_diffrn_data_frame.binary_id'
_item.category_id diffrn_data_frame
_item.mandatory_code implicit
_item_aliases.alias_name '_diffrn_frame_data.binary_id'
_item_aliases.dictionary cif_img.dic
_item_aliases.version 1.0
_item_type.code int
save_
save__diffrn_data_frame.detector_element_id
_item_description.description
;
This item is a pointer to _diffrn_detector_element.id
in the DIFFRN_DETECTOR_ELEMENT category.
;
_item.name '_diffrn_data_frame.detector_element_id'
_item.category_id diffrn_data_frame
_item.mandatory_code yes
_item_aliases.alias_name '_diffrn_frame_data.detector_element_id'
_item_aliases.dictionary cif_img.dic
_item_aliases.version 1.0
_item_type.code code
save_
save__diffrn_data_frame.id
_item_description.description
;
The value of _diffrn_data_frame.id must uniquely identify
each complete frame of data.
;
loop_
_item.name
_item.category_id
_item.mandatory_code
'_diffrn_data_frame.id' diffrn_data_frame yes
'_diffrn_refln.frame_id' diffrn_refln yes
'_diffrn_scan.frame_id_start' diffrn_scan yes
'_diffrn_scan.frame_id_end' diffrn_scan yes
'_diffrn_scan_frame.frame_id' diffrn_scan_frame yes
'_diffrn_scan_frame_axis.frame_id'
diffrn_scan_frame_axis
yes
_item_aliases.alias_name '_diffrn_frame_data.id'
_item_aliases.dictionary cif_img.dic
_item_aliases.version 1.0
_item_type.code code
loop_
_item_linked.child_name
_item_linked.parent_name
'_diffrn_refln.frame_id' '_diffrn_data_frame.id'
'_diffrn_scan.frame_id_start' '_diffrn_data_frame.id'
'_diffrn_scan.frame_id_end' '_diffrn_data_frame.id'
'_diffrn_scan_frame.frame_id' '_diffrn_data_frame.id'
'_diffrn_scan_frame_axis.frame_id'
'_diffrn_data_frame.id'
save_
##########################################################################
# The following is a restatement of the mmCIF DIFFRN_DETECTOR, #
# DIFFRN_MEASUREMENT and DIFFRN_RADIATION categories, modified for #
# the CBF/imgCIF extensions #
##########################################################################
###################
# DIFFRN_DETECTOR #
###################
save_DIFFRN_DETECTOR
_category.description
; Data items in the DIFFRN_DETECTOR category describe the
detector used to measure the scattered radiation, including
any analyser and post-sample collimation.
;
_category.id diffrn_detector
_category.mandatory_code no
loop_
_category_key.name '_diffrn_detector.diffrn_id'
'_diffrn_detector.id'
loop_
_category_group.id 'inclusive_group'
'diffrn_group'
loop_
_category_examples.detail
_category_examples.case
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
;
Example 1 - based on PDB entry 5HVP and laboratory records for the
structure corresponding to PDB entry 5HVP
;
;
_diffrn_detector.diffrn_id 'd1'
_diffrn_detector.detector 'multiwire'
_diffrn_detector.type 'Siemens'
;
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
save_
save__diffrn_detector.details
_item_description.description
; A description of special aspects of the radiation detector.
;
_item.name '_diffrn_detector.details'
_item.category_id diffrn_detector
_item.mandatory_code no
_item_aliases.alias_name '_diffrn_detector_details'
_item_aliases.dictionary cif_core.dic
_item_aliases.version 2.0.1
_item_type.code text
_item_examples.case
; Need new example here.
;
save_
save__diffrn_detector.detector
_item_description.description
; The general class of the radiation detector.
;
_item.name '_diffrn_detector.detector'
_item.category_id diffrn_detector
_item.mandatory_code no
loop_
_item_aliases.alias_name
_item_aliases.dictionary
_item_aliases.version '_diffrn_radiation_detector'
cifdic.c91
1.0
'_diffrn_detector'
cif_core.dic
2.0
_item_type.code text
loop_
_item_examples.case 'photographic film'
'scintillation counter'
'CCD plate'
'BF~3~ counter'
save_
save__diffrn_detector.diffrn_id
_item_description.description
; This data item is a pointer to _diffrn.id in the DIFFRN
category.
The value of _diffrn.id uniquely defines a set of
diffraction data.
;
_item.name '_diffrn_detector.diffrn_id'
_item.mandatory_code yes
save_
save__diffrn_detector.dtime
_item_description.description
; The deadtime in microseconds of the detectors used to measure
the diffraction intensities.
;
_item.name '_diffrn_detector.dtime'
_item.category_id diffrn_detector
_item.mandatory_code no
loop_
_item_aliases.alias_name
_item_aliases.dictionary
_item_aliases.version '_diffrn_radiation_detector_dtime'
cifdic.c91
1.0
'_diffrn_detector_dtime'
cif_core.dic
2.0
loop_
_item_range.maximum
_item_range.minimum . 0.0
0.0 0.0
_item_type.code float
_item_units.code microseconds
save_
save__diffrn_detector.id
_item_description.description
;
The value of _diffrn_detector.id must uniquely identify
each detector used to collect each diffraction data set.
If the value of _diffrn_detector.id is not given, it is
implicitly equal to the value of _diffrn_detector.diffrn_id
;
loop_
_item.name
_item.category_id
_item.mandatory_code
'_diffrn_detector.id' diffrn_detector implicit
'_diffrn_detector_axis.detector_id'
diffrn_detector_axis yes
loop_
_item_linked.child_name
_item_linked.parent_name
'_diffrn_detector_axis.detector_id'
'_diffrn_detector.id'
_item_type.code code
save_
save__diffrn_detector.number_of_axes
_item_description.description
;
The value of _diffrn_detector.number_of_axes gives the
number of axes of the positioner for the detector identified
by _diffrn_detector.id
The word "positioner" is a general term used in instrumentation
design for devices that are used to change the positions of
portions of apparatus by linear translation, rotation, or
combinations of such motions.
Axes which are used to provide a coordinate system for the
face of an area detetctor should not be counted for this
data item.
The description of each axis should be provided by entries
in DIFFRN_DETECTOR_AXIS.
;
_item.name '_diffrn_detector.number_of_axes'
_item.category_id diffrn_detector
_item.mandatory_code no
loop_
_item_range.maximum
_item_range.minimum . 1
1 1
_item_type.code int
save_
save__diffrn_detector.type
_item_description.description
; The make, model or name of the detector device used.
;
_item.name '_diffrn_detector.type'
_item.category_id diffrn_detector
_item.mandatory_code no
_item_aliases.alias_name '_diffrn_detector_type'
_item_aliases.dictionary cif_core.dic
_item_aliases.version 2.0.1
_item_type.code text
save_
########################
# DIFFRN_DETECTOR_AXIS #
########################
save_DIFFRN_DETECTOR_AXIS
_category.description
;
Data items in the DIFFRN_DETECTOR_AXIS category associate
axes with detectors.
;
_category.id diffrn_detector_axis
_category.mandatory_code no
loop_
_category_key.name '_diffrn_detector_axis.detector_id'
'_diffrn_detector_axis.axis_id'
loop_
_category_group.id 'inclusive_group'
'diffrn_group'
save_
save__diffrn_detector_axis.axis_id
_item_description.description
;
This data item is a pointer to _axis.id in
the AXIS category.
;
_item.name '_diffrn_detector_axis.axis_id'
_item.category_id diffrn_detector_axis
_item.mandatory_code yes
_item_type.code code
save_
save__diffrn_detector_axis.detector_id
_item_description.description
;
This data item is a pointer to _diffrn_detector.id in
the DIFFRN_DETECTOR category.
This item was previously named '_diffrn_detector_axis.id'
which is now a deprecated name. The old name is
provided as an alias, but should not be used for new work.
;
_item.name '_diffrn_detector_axis.detector_id'
_item.category_id diffrn_detector_axis
_item.mandatory_code yes
_item_aliases.alias_name '_diffrn_detector_axis.id'
_item_aliases.dictionary cif_img.dic
_item_aliases.version 1.0
save_
###########################
# DIFFRN_DETECTOR_ELEMENT #
###########################
save_DIFFRN_DETECTOR_ELEMENT
_category.description
;
Data items in the DIFFRN_DETECTOR_ELEMENT category record
the details about spatial layout and other characteristics
of each element of a detector which may have multiple elements.
In most cases, the more detailed information provided
in ARRAY_STRUCTURE_LIST and ARRAY_STRUCTURE_LIST_AXIS
are preferable to simply providing the centre.
;
_category.id diffrn_detector_element
_category.mandatory_code no
loop_
_category_key.name '_diffrn_detector_element.id'
'_diffrn_detector_element.detector_id'
loop_
_category_group.id 'inclusive_group'
'array_data_group'
loop_
_category_examples.detail
_category_examples.case
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
;
Example 1 - Detector d1 is composed of four CCD detector elements,
each 200 mm by 200 mm, arranged in a square. in the pattern
1 2
*
3 4
Note that the beam center is slightly off of each of the
detector elements, just beyond the lower right corner of 1,
the lower left corner of 2, the upper right corner of 3 and
the upper left corner of 4.
;
;
loop_
_diffrn_detector_element.id
_diffrn_detector_element.detector_id
_diffrn_detector_element.center[1]
_diffrn_detector_element.center[2]
d1 d1_ccd_1 201.5 -1.5
d1 d1_ccd_2 -1.8 -1.5
d1 d1_ccd_3 201.6 201.4
d1 d1_ccd_4 -1.7 201.5
;
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
save_
save__diffrn_detector_element.center[1]
_item_description.description
;
The value of _diffrn_detector_element.center[1] is the X
component of the distortion-corrected beam-center in mm from the
(0, 0) (lower left) corner of the detector element viewed from
the sample side.
;
_item.name '_diffrn_detector_element.center[1]'
_item.category_id diffrn_detector_element
_item.mandatory_code no
_item_default.value 0.0
_item_sub_category.id vector
_item_type.code float
_item_units.code millimetres
save_
save__diffrn_detector_element.center[2]
_item_description.description
;
The value of _diffrn_detector_element.center[2] is the Y
component of the distortion-corrected beam-center in mm from the
(0, 0) (lower left) corner of the detector element viewed from
the sample side.
;
_item.name '_diffrn_detector_element.center[2]'
_item.category_id diffrn_detector_element
_item.mandatory_code no
_item_default.value 0.0
_item_sub_category.id vector
_item_type.code float
_item_units.code millimetres
save_
save__diffrn_detector_element.id
_item_description.description
;
The value of _diffrn_detector_element.id must uniquely identify
each element of a detector.
;
loop_
_item.name
_item.category_id
_item.mandatory_code
'_diffrn_detector_element.id'
diffrn_detector_element
yes
_item_type.code code
loop_
_item_linked.child_name
_item_linked.parent_name
'_diffrn_data_frame.detector_element_id'
'_diffrn_detector_element.id'
save_
save__diffrn_detector_element.detector_id
_item_description.description
;
This item is a pointer to _diffrn_detector.id
in the DIFFRN_DETECTOR category.
;
_item.name '_diffrn_detector_element.detector_id'
_item.category_id diffrn_detector_element
_item.mandatory_code yes
_item_type.code code
save_
########################
## DIFFRN_MEASUREMENT ##
########################
save_DIFFRN_MEASUREMENT
_category.description
; Data items in the DIFFRN_MEASUREMENT category record details
about the device used to orient and/or position the crystal
during data measurement and the manner in which the diffraction
data were measured.
;
_category.id diffrn_measurement
_category.mandatory_code no
loop_
_category_key.name '_diffrn_measurement.device'
'_diffrn_measurement.diffrn_id'
'_diffrn_measurement.id'
loop_
_category_group.id 'inclusive_group'
'diffrn_group'
loop_
_category_examples.detail
_category_examples.case
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
;
Example 1 - based on PDB entry 5HVP and laboratory records for the
structure corresponding to PDB entry 5HVP
;
;
_diffrn_measurement.diffrn_id 'd1'
_diffrn_measurement.device '3-circle camera'
_diffrn_measurement.device_type 'Supper model x'
_diffrn_measurement.device_details 'none'
_diffrn_measurement.method 'omega scan'
_diffrn_measurement.details
; Need new example here
;
;
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
;
Example 2 - based on data set TOZ of Willis, Beckwith & Tozer [(1991).
Acta Cryst. C47, 2276-2277].
;
;
_diffrn_measurement.diffrn_id 's1'
_diffrn_measurement.device_type 'Philips PW1100/20 diffractometer'
_diffrn_measurement.method 'theta/2theta (\q/2\q)'
;
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
save_
save__diffrn_measurement.device
_item_description.description
; The general class of goniometer or device used to support and
orient the specimen.
If the value of _diffrn_measurement.device is not given, it is
implicitly equal to the value of _diffrn_measurement.diffrn_id
Either '_diffrn_measurement.device' or '_diffrn_measurement.id'
may be used to link to other categories. If the experimental
setup admits multiple devices, then '_diffrn_measurement.id'
is used to provide a unique link.
;
loop_
_item.name
_item.category_id
_item.mandatory_code
'_diffrn_measurement.device' diffrn_measurement implicit
'_diffrn_measurement_axis.measurement_device'
diffrn_measurement_axis implicit
loop_
_item_linked.child_name
_item_linked.parent_name
'_diffrn_measurement_axis.measurement_device'
'_diffrn_measurement.device'
_item_aliases.alias_name '_diffrn_measurement_device'
_item_aliases.dictionary cif_core.dic
_item_aliases.version 2.0.1
_item_type.code text
loop_
_item_examples.case '3-circle camera'
'4-circle camera'
'kappa-geometry camera'
'oscillation camera'
'precession camera'
save_
save__diffrn_measurement.device_details
_item_description.description
; A description of special aspects of the device used to measure
the diffraction intensities.
;
_item.name '_diffrn_measurement.device_details'
_item.category_id diffrn_measurement
_item.mandatory_code no
_item_aliases.alias_name '_diffrn_measurement_device_details'
_item_aliases.dictionary cif_core.dic
_item_aliases.version 2.0.1
_item_type.code text
_item_examples.case
; commercial goniometer modified locally to
allow for 90\% \t arc
;
save_
save__diffrn_measurement.device_type
_item_description.description
; The make, model or name of the measurement device
(goniometer) used.
;
_item.name '_diffrn_measurement.device_type'
_item.category_id diffrn_measurement
_item.mandatory_code no
_item_aliases.alias_name '_diffrn_measurement_device_type'
_item_aliases.dictionary cif_core.dic
_item_aliases.version 2.0.1
_item_type.code text
loop_
_item_examples.case 'Supper model q'
'Huber model r'
'Enraf-Nonius model s'
'homemade'
save_
save__diffrn_measurement.diffrn_id
_item_description.description
; This data item is a pointer to _diffrn.id in the DIFFRN
category.
;
_item.name '_diffrn_measurement.diffrn_id'
_item.mandatory_code yes
save_
save__diffrn_measurement.details
_item_description.description
; A description of special aspects of the intensity measurement.
;
_item.name '_diffrn_measurement.details'
_item.category_id diffrn_measurement
_item.mandatory_code no
_item_aliases.alias_name '_diffrn_measurement_details'
_item_aliases.dictionary cif_core.dic
_item_aliases.version 2.0.1
_item_type.code text
_item_examples.case
; 440 frames, 0.20 degrees, 150 sec, detector
distance 12 cm, detector angle 22.5 degrees
;
save_
save__diffrn_measurement.id
_item_description.description
;
The value of _diffrn_measurement.id must uniquely identify
the set of mechanical characteristics of the device used to
orient and/or position the sample used during collection
of each diffraction data set.
If the value of _diffrn_measurement.id is not given, it is
implicitly equal to the value of _diffrn_measurement.diffrn_id
Either '_diffrn_measurement.device' or '_diffrn_measurement.id'
may be used to link to other categories. If the experimental
setup admits multiple devices, then '_diffrn_measurement.id'
is used to provide a unique link.
;
loop_
_item.name
_item.category_id
_item.mandatory_code
'_diffrn_measurement.id' diffrn_measurement implicit
'_diffrn_measurement_axis.measurement_id'
diffrn_measurement_axis implicit
loop_
_item_linked.child_name
_item_linked.parent_name
'_diffrn_measurement_axis.measurement_id'
'_diffrn_measurement.id'
_item_type.code code
save_
save__diffrn_measurement.method
_item_description.description
; Method used to measure intensities.
;
_item.name '_diffrn_measurement.method'
_item.category_id diffrn_measurement
_item.mandatory_code no
_item_aliases.alias_name '_diffrn_measurement_method'
_item_aliases.dictionary cif_core.dic
_item_aliases.version 2.0.1
_item_type.code text
_item_examples.case 'profile data from theta/2theta (\q/2\q) scans'
save_
save__diffrn_measurement.number_of_axes
_item_description.description
;
The value of _diffrn_measurement.number_of_axes gives the
number of axes of the positioner for the goniometer or
other sample orientation or positioning device identified
by _diffrn_measurement.id
The description of the axes should be provided by entries in
DIFFRN_MEASUREMENT_AXIS.
;
_item.name '_diffrn_measurement.number_of_axes'
_item.category_id diffrn_measurement
_item.mandatory_code no
loop_
_item_range.maximum
_item_range.minimum . 1
1 1
_item_type.code int
save_
save__diffrn_measurement.specimen_support
_item_description.description
; The physical device used to support the crystal during data
collection.
;
_item.name '_diffrn_measurement.specimen_support'
_item.category_id diffrn_measurement
_item.mandatory_code no
_item_aliases.alias_name '_diffrn_measurement_specimen_support'
_item_aliases.dictionary cif_core.dic
_item_aliases.version 2.0.1
_item_type.code text
loop_
_item_examples.case 'glass capillary'
'quartz capillary'
'fiber'
'metal loop'
save_
###########################
# DIFFRN_MEASUREMENT_AXIS #
###########################
save_DIFFRN_MEASUREMENT_AXIS
_category.description
;
Data items in the DIFFRN_MEASUREMENT_AXIS category associate
axes with goniometers.
;
_category.id diffrn_measurement_axis
_category.mandatory_code no
loop_
_category_key.name '_diffrn_measurement_axis.measurement_device'
'_diffrn_measurement_axis.measurement_id'
'_diffrn_measurement_axis.axis_id'
loop_
_category_group.id 'inclusive_group'
'diffrn_group'
save_
save__diffrn_measurement_axis.axis_id
_item_description.description
;
This data item is a pointer to _axis.id in
the AXIS category.
;
_item.name '_diffrn_measurement_axis.axis_id'
_item.category_id diffrn_measurement_axis
_item.mandatory_code yes
_item_type.code code
save_
save__diffrn_measurement_axis.measurement_device
_item_description.description
;
This data item is a pointer to _diffrn_measurement.device in
the DIFFRN_MEASUREMENT category.
;
_item.name '_diffrn_measurement_axis.measurement_device'
_item.category_id diffrn_measurement_axis
_item.mandatory_code implicit
save_
save__diffrn_measurement_axis.measurement_id
_item_description.description
;
This data item is a pointer to _diffrn_measurement.id in
the DIFFRN_MEASUREMENT category.
This item was previously named '_diffrn_measurement_axis.id'
which is now a deprecated name. The old name is
provided as an alias, but should not be used for new work.
;
_item.name '_diffrn_measurement_axis.measurement_id'
_item.category_id diffrn_measurement_axis
_item_aliases.alias_name '_diffrn_measurement_axis.id'
_item_aliases.dictionary cif_img.dic
_item_aliases.version 1.0.00
_item.mandatory_code implicit
save_
####################
# DIFFRN_RADIATION #
####################
save_DIFFRN_RADIATION
_category.description
; Data items in the DIFFRN_RADIATION category describe
the radiation used in measuring diffraction intensities,
its collimation and monochromatisation before the sample.
Post-sample treatment of the beam is described by data
items in the DIFFRN_DETECTOR category.
;
_category.id diffrn_radiation
_category.mandatory_code no
_category_key.name '_diffrn_radiation.diffrn_id'
loop_
_category_group.id 'inclusive_group'
'diffrn_group'
loop_
_category_examples.detail
_category_examples.case
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
;
Example 1 - based on PDB entry 5HVP and laboratory records for the
structure corresponding to PDB entry 5HVP
;
;
_diffrn_radiation.diffrn_id 'set1'
_diffrn_radiation.collimation '0.3 mm double pinhole'
_diffrn_radiation.monochromator 'graphite'
_diffrn_radiation.type 'Cu K\a'
_diffrn_radiation.wavelength_id 1
;
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
;
Example 2 - based on data set TOZ of Willis, Beckwith & Tozer [(1991).
Acta Cryst. C47, 2276-2277].
;
;
_diffrn_radiation.wavelength_id 1
_diffrn_radiation.type 'Cu K\a'
_diffrn_radiation.monochromator 'graphite'
;
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
save_
save__diffrn_radiation.collimation
_item_description.description
; The collimation or focusing applied to the radiation.
;
_item.name '_diffrn_radiation.collimation'
_item.category_id diffrn_radiation
_item.mandatory_code no
_item_aliases.alias_name '_diffrn_radiation_collimation'
_item_aliases.dictionary cif_core.dic
_item_aliases.version 2.0.1
_item_type.code text
loop_
_item_examples.case '0.3 mm double-pinhole'
'0.5 mm'
'focusing mirrors'
save_
save__diffrn_radiation.diffrn_id
_item_description.description
; This data item is a pointer to _diffrn.id in the DIFFRN
category.
;
_item.name '_diffrn_radiation.diffrn_id'
_item.mandatory_code yes
save_
save__diffrn_radiation.div_x_source
_item_description.description
; Beam crossfire in degrees parallel to the laboratory X axis
(see AXIS category).
This is a characteristic of the xray beam as it illuminates
the sample (or specimen) after all monochromation and
collimation.
This is the esd of the directions of photons in the X-Z plane
around the mean source beam direction.
Note that some synchrotrons specify this value in milliradians,
in which case a conversion would be needed. To go from a
value in milliradians to a value in degrees, multiply by 0.180
and divide by Pi.
;
_item.name '_diffrn_radiation.div_x_source'
_item.category_id diffrn_radiation
_item.mandatory_code no
_item_type.code float
_item_units.code degrees
save_
save__diffrn_radiation.div_y_source
_item_description.description
; Beam crossfire in degrees parallel to the laboratory Y axis
(see AXIS category).
This is a characteristic of the xray beam as it illuminates
the sample (or specimen) after all monochromation and
collimation.
This is the esd of the directions of photons in the Y-Z plane
around the mean source beam direction.
Note that some synchrotrons specify this value in milliradians,
in which case a conversion would be needed. To go from a
value in milliradians to a value in degrees, multiply by 0.180
and divide by Pi.
;
_item.name '_diffrn_radiation.div_y_source'
_item.category_id diffrn_radiation
_item.mandatory_code no
_item_type.code float
_item_units.code degrees
_item_default.value 0.0
save_
save__diffrn_radiation.div_x_y_source
_item_description.description
; Beam crossfire correlation degrees**2 between the
crossfire laboratory X-axis component and the crossfire
laboratory Y-axis component (see AXIS category).
This is a characteristic of the xray beam as it illuminates
the sample (or specimen) after all monochromation and
collimation.
This is the mean of the products of the deviations of the
directin of each photons in X-Z plane times the deviations
of the direction of the same photon in the Y-Z plane
around the mean source beam direction. This will be zero
for uncorrelated crossfire.
Note that some synchrotrons specify this value in
milliradians**2, in which case a conversion would be needed.
To go from a value in milliradians**2 to a value in
degrees**2, multiply by 0.180**2 and divide by Pi**2.
;
_item.name '_diffrn_radiation.div_x_y_source'
_item.category_id diffrn_radiation
_item.mandatory_code no
_item_type.code float
_item_units.code degrees_squared
_item_default.value 0.0
save_
save__diffrn_radiation.filter_edge
_item_description.description
; Absorption edge in angstroms of the radiation filter used.
;
_item.name '_diffrn_radiation.filter_edge'
_item.category_id diffrn_radiation
_item.mandatory_code no
_item_aliases.alias_name '_diffrn_radiation_filter_edge'
_item_aliases.dictionary cif_core.dic
_item_aliases.version 2.0.1
loop_
_item_range.maximum
_item_range.minimum . 0.0
0.0 0.0
_item_type.code float
_item_units.code angstroms
save_
save__diffrn_radiation.inhomogeneity
_item_description.description
; Half-width in millimetres of the incident beam in the
direction perpendicular to the diffraction plane.
;
_item.name '_diffrn_radiation.inhomogeneity'
_item.category_id diffrn_radiation
_item.mandatory_code no
_item_aliases.alias_name '_diffrn_radiation_inhomogeneity'
_item_aliases.dictionary cif_core.dic
_item_aliases.version 2.0.1
loop_
_item_range.maximum
_item_range.minimum . 0.0
0.0 0.0
_item_type.code float
_item_units.code millimetres
save_
save__diffrn_radiation.monochromator
_item_description.description
; 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.
;
_item.name '_diffrn_radiation.monochromator'
_item.category_id diffrn_radiation
_item.mandatory_code no
_item_aliases.alias_name '_diffrn_radiation_monochromator'
_item_aliases.dictionary cif_core.dic
_item_aliases.version 2.0.1
_item_type.code text
loop_
_item_examples.case 'Zr filter'
'Ge 220'
'none'
'equatorial mounted graphite'
save_
save__diffrn_radiation.polarisn_norm
_item_description.description
; The angle in degrees, as viewed from the specimen, between the
perpendicular component of the polarisation and the diffraction
plane. See _diffrn_radiation_polarisn_ratio.
;
_item.name '_diffrn_radiation.polarisn_norm'
_item.category_id diffrn_radiation
_item.mandatory_code no
_item_aliases.alias_name '_diffrn_radiation_polarisn_norm'
_item_aliases.dictionary cif_core.dic
_item_aliases.version 2.0.1
loop_
_item_range.maximum
_item_range.minimum . 0.0
0.0 0.0
_item_type.code float
_item_units.code degrees
save_
save_