Chemical Crystallography

Note on DIALS versions: The small_molecule feature described is available in DIALS versions >3.29. DIALS versions 3.29 - 3.26 have the composition parameter.

Data from small molecule (or chemical crystallography) experiments can also be processed using xia2.multiplex. To enable relevant options for small molecule data processing, set the parameter small_molecule=True. This will trigger a full symmetry analysis including glide planes, mirror planes etc., i.e. the space group will not be restricted to MX-only space groups. Setting the small_molecule option will also output SHELX-compatible files. If a user specified composition is provided with the composition parameter (e.g. composition=C10H14O4Cu), this will be written into the SHELX files. If no composition is provided, a dummy composition of “CH” will be used. Running SHELXT on your output files will provide an estimation of the number of atoms, from which you can assign chemical identity later using your preferred refinement program.