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The Crystallographic Information File
Version 1.1 Specification
Draft of 10 July 2002
The Crystallographic Information File (CIF) is an archiving
and information interchange standard for crystallographic and
related structural science data promoted by the International
Union for Crystallography. It is a restricted-syntax
implementation of the general Self-Defining Text Archival and
Retrieval (STAR) File format (Hall, 1991;
Hall & Spadaccini, 1994).
Names and attributes of standard data items are defined in
publicly available collections known as data dictionaries under
the authority of an IUCr Committee (COMCIFS).
Conformance
Any file claiming to be a crystallographic information file must conform
to the specifications as herein laid out. Since CIF is an extensible
format, files may be considered valid where they contain legal extensions
to content beyond the standard data items as defined in public
dictionaries. It is also inevitable that CIF software will be written to
exploit various subsets of the information that may be conveyed in a CIF,
and therefore not all software will be required to handle all content in a
specific manner.
However, all CIF conformant software must as a minimum be able to
locate, extract or write data items in strict accordance with the
syntax rules that form part of this
specification.
Hall, S. R. (1991). "The STAR File: A New
Format for Electronic Data Transfer and Archiving", J.
Chem. Inform. Comp. Sci., 31, 326-333.
Hall, S. R., Allen, F. H. and Brown, I. D.
(1991). "The Crystallographic Information File (CIF): A New
Standard Archive File for Crystallography", Acta
Cryst., A47, 655-685.