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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. 3.4, p. 134
Section 3.4.3.2.1. Refinement techniques and results
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Departamento de Física de la Materia Condensada, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apartado 644, 48080 Bilbao, Spain |
New data items in this category are as follows:
![[Scheme scheme12]](/schemes/Gach3o4scheme12.gif)
During the early stages of the development of the msCIF dictionary, several sets of data items were defined to accommodate the need to specify residual R factors for the different sets of main reflections and satellite reflections. It was then recognized that the binning of reflection classes had more general application, and these new data items were transferred to the core CIF dictionary, where, of course, they are still available for use in an msCIF.
The new items in the REFINE category in the msCIF dictionary are specific to the refinement of modulated structures. _refine_ls_mod_func_description allows a free-text description of the types of modulation present in the structural model and how they are handled. The treatment of hydrogen-atom modulation parameters is specified by _refine_ls_mod_hydrogen_treatment. Information on an overall phason correction (the use of which should in general be discouraged) may be given using the _refine_ls_mod_overall_phason_* items.
