Overview
The EXPDTA record presents information about the experiment.
The EXPDTA record identifies the experimental technique used. This may refer to the type of radiation and sample, or include the spectroscopic or modeling technique. Permitted values include:
ELECTRON DIFFRACTION
FIBER DIFFRACTION
FLUORESCENCE TRANSFER
NEUTRON DIFFRACTION
NMR
THEORETICAL MODEL
X-RAY DIFFRACTION
Record Format
COLUMNS DATA TYPE FIELD DEFINITION
-------------------------------------------------------------------------------
1 - 6 Record name "EXPDTA"
9 - 10 Continuation continuation Allows concatenation of multiple
records.
11 - 70 SList technique The experimental technique(s) with
optional comment describing the
sample or experiment.
Details
* EXPDTA is mandatory and appears in all entries.
* The technique must match one of the permitted values. See above.
* If more than one model appears in the entry, the number of models included must be stated.
* If only one model appears in the entry, its significance must be stated, such as it being a minimized average or regularized mean structure.
* If more than one technique was used for the structure determination and is being represented in the entry, EXPDTA presents the techniques as a semi-colon separated list. Each technique may have a comment, which appears before the semi-colon.
Verification/Validation/Value Authority Control
The verification program checks that the EXPDTA record appears in the entry and that the technique matches one of the allowed values. It also checks that the relevant standard REMARK is added in the case of NMR, fiber, or theoretical modeling studies, and that the correct CRYST1 and SCALE are used in these cases. If an entry contains multiple models, the verification program checks for the correct number of matching MODEL/ENDMDL records.
Relationships to Other Record Types
If the experiment is an NMR, fiber, or theoretical modeling study, this may be stated in the TITLE, and the appropriate EXPDTA and REMARK records should appear. Specific details of the data collection and experiment appear in the REMARKs.
In the case of a polycrystalline fiber diffraction study, CRYST1 and SCALE contain the normal unit cell data.
Example
1 2 3 4 5 6 7
1234567890123456789012345678901234567890123456789012345678901234567890
EXPDTA X-RAY DIFFRACTION
EXPDTA NEUTRON DIFFRACTION; X-RAY DIFFRACTION
EXPDTA NMR, 32 STRUCTURES
EXPDTA NMR, REGULARIZED MEAN STRUCTURE
EXPDTA THEORETICAL MODEL
EXPDTA FIBER DIFFRACTION, FIBER
EXPDTA FIBER DIFFRACTION, POLYCRYSTALLINE SAMPLE