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Macromolecular dictionary (mmCIF) version 2.0.09

_chemical.absolute_configuration

Name:
'_chemical.absolute_configuration'

Definition:

   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,
           908-915. (http://www.iucr.org/paper?sh0129)
        Flack, H. D. & Bernardinelli, G. (2000). J. Appl. Cryst.
           33, 1143-1148. (http://www.iucr.org/paper?ks0021)

Type: code

Mandatory item: no

Alias:
_chemical_absolute_configuration (cif_core.dic version 2.3)
The data value must be one of the following:


rm
absolute configuration established by the structure determination of a compound containing a chiral reference molecule of known absolute configuration

ad
absolute configuration established by anomalous-dispersion effects in diffraction measurements on the crystal

rmad
absolute configuration established by the structure determination of a compound containing a chiral reference molecule of known absolute configuration and confirmed by anomalous-dispersion effects in diffraction measurements on the crystal

syn
absolute configuration has not been established by anomalous-dispersion effects in diffraction measurements on the crystal. The enantiomer has been assigned by reference to an unchanging chiral centre in the synthetic procedure

unk
absolute configuration is unknown, there being no firm chemical evidence for its assignment to hand and it having not been established by anomalous-dispersion effects in diffraction measurements on the crystal. An arbitrary choice of enantiomer has been made

.
inapplicable

Category: chemical