Describes CIF, the data exchange standard of crystallography. Provides: information for scientists who wish to record or use the results of a single-crystal or powder diffraction experiment; the data ontology necessary for designing interoperable computer applications; accompanying software including machine-readable CIF dictionaries, libraries and utility programs.
An essential guide and reference to CIF for programmers, data managers handling crystal-structure information and practising crystallographers.
A description of special aspects of the weighting scheme used in the least-squares refinement. Used to describe the weighting when the value of _refine_ls_weighting_scheme is specified as 'calc'.Example:
; Sigdel model of Konnert-Hendrickson: Sigdel = Afsig + Bfsig*(sin(\q)/\l - 1/6) Afsig = 22.0, Bfsig = 150.0 at the beginning of refinement. Afsig = 16.0, Bfsig = 60.0 at the end of refinement. ;