From XDSwiki
Revision as of 17:36, 18 November 2007 by Kay (talk | contribs) (New page: == General guidelines for obtaining a good result from XDS == * read XDS.INP * for good indexing, follow XDS.INP#Keywords which affect whether indexing will succeed * for good c...)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to navigationJump to search

General guidelines for obtaining a good result from XDS

Final polishing

  • After running through all steps of XDS (including space group determination), one might want to
grep -v REIDX XDS.INP > XDS.INP.new

and re-run the INTEGRATE and CORRECT steps. This has the advantage that the refined geometry parameters (from CORRECT) are recycled into INTEGRATE, which sometimes leads to better R-factors.

  • look through the list of reflections labeled as "aliens" in CORRECT.LP. Decide whether they follow a slowly decaying non-Wilson distribution (resulting in many reflections with Z > 8 instead of none in the case of a perfect Wilson distribution), or whether the top ones are true outliers. The latter occurs most often from ice reflections (these may even be there when no ice rings are visible). My personal rule of thumb is that when the integer parts of Z cover the numbers 8, 9, ... n, but there are no reflections with Z = n+1, then I consider all reflections with Z > n+1 as outliers. These are then put (i.e. copied) into REMOVE.HKL, and CORRECT is re-run.