Crysfire / Chekcell: indexing powder Protein data
Even on rescaled data, if Crysfire and the various indexing programs do not find the “true cell”, Chekcell and possibly can find a derivative cell which LePage (combined with Chekcell’s “parsimony and superflous reflections” criteria), can find the true cell. In the case of reindexing of the protein data:
- Crysfire and Dicvol finds
- 73.2645 70.5256 40.7430 90.000 90.000 90.000 Orthorhomic
- P222 or PMM2 or PMMM : 157 hkls to match 41 reflections
- LePage followed by Chekcell “parsimony check” then finds:
- 81.449 81.449 73.265 90 .000 90.000 120.00 Rhombohedral
- 52.988 52.988 52.988 100.45 100.45 100.45 Rhombohedral
- R-3 or R3 etc : 60 hkls to match 41 reflections