Oxford Diffraction data

(according to a posting on CCP4BB on Feb 5, 2010)

CrysAlisPro is the name Oxford Diffraction uses to describe their instrument control and data reduction software; it writes out frames in Oxford format and can convert its frames to XDS, (i)MOSFLM and MAR compatible formats. In the standard Oxford Diffraction system, the frames are integrated by the CrysAlisPro ‘dc proffit module’ which outputs reflections in a variety of hkl formats (hkl, cif, mtz, Bruker). EVAL, XDS, d*TREK, CysAlisPro and possibly other integration programs can also process Bruker frames, but only SAINT, EVAL and CrysAlisPro can currently integrate the diffraction patterns of non-merohedrally twinned and modulated structures (in up to 6 dimensions). For scaling, Oxford Diffraction provides SCALE3 ABSPACK (for scaling normal and modulated structures and non-merohedral twins). SCALE3 ABSPACK provides a similar functionality to SCALEPACK, SCALA and additionally also provides a detector sensitivity correction similar to Wolfgang Kabsch’s XSCALE. It outputs merged or unmerged reflection lists in various ASCII formats that can be converted to .mtz by, for example, the CCP4 program COMBAT. SCALE3 ABSPACK provides the empirical corrections for non-merohedral twins. The TWIN FINALIZER writes SHELX HKLF 5 format .hkl files for refinement of non-merohedral twins with SHELXL and can also produce 'detwinned' HKLF 4 format files that can be input to CCP4 by COMBAT and then treated in the same way as data from untwinned crystals. These are better quality than conventional 'detwinned' data because TWIN FINALIZER de-convolutes overlapping reflections.