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Core CIF Dictionary version 2.3




Category: atom_site

Data type: char

Must appear in a looped list containing '_atom_site_label'

Related item(s), related function(s):
'_atom_site_refinement_flags_posn' replace '_atom_site_refinement_flags_adp' replace '_atom_site_refinement_flags_occupancy' replace

Permitted values:

. 'no refinement constraints'
S 'special position constraint on site'
G 'rigid group refinement of site'
R 'riding-atom site attached to non-riding atom'
D 'distance or angle restraint on site'
T 'thermal displacement constraints'
U 'Uiso or Uij restraint (rigid bond)'
P 'partial occupancy constraint'


A concatenated series of single-letter 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 It has been replaced by _atom_site_refinement_flags_posn, *_adp and *_occupancy.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.

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