International
Tables for Crystallography Volume G Definition and exchange of crystallographic data Edited by S. R. Hall and B. McMahon © International Union of Crystallography 2006 |
International Tables for Crystallography (2006). Vol. G. ch. 2.2, p. 27
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(32) Save frames are permitted in CIFs, but expressly for the purpose of encapsulating data-name definitions within data dictionaries. No reference to these save frames is envisaged, and the save-frame reference code permitted in STAR is not used. This means that unquoted character strings commencing with the $ character may not be interpreted as save-frame codes in CIF. Use of such unquoted character strings is reserved to guard against subsequent relaxation of this constraint.