Section 3.4.3.2. Analysis

New data items in this category are as follows:

REFINE

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.

New data items in these categories are as follows:

(a) REFLN

(b) REFLNS

As with the _diffrn_refln_* and _diffrn_reflns_* items (Section 3.4.3.1.2), these data names extend the corresponding core data items into the higher-dimensional space used in the treatment of modulated structures and composites. They apply to the list of reflections used in the refinement, as distinct from the experimentally collected set of intensities described by the _diffrn_* data items.