Hi Jan, While the results from integration with a triclinic lattice should be fine (you appear to be happy with them) the integration with a cubic lattice thing is odd. I just ran XDS on a cubic insulin data set via xia2 and - even when the symmetry is set - the cell constant is refined. This is cI like the example you describe below. When working like this however I do explicitly set REFINE(INTEGRATE)=ORIENTATION CELL as I like that to be refined, while keeping the experimental hardware settings at the postrefined values.
What have you set REFINE(INTEGRATE)= to in XDS.INP? Cheers, Graeme 2009/10/14 Jan Abendroth <jan.abendr...@gmail.com>: > Hi all, > thanks a lot for numerous replies. > Graeme's suggestion to integrate in triclinic and let CORRECT sort out the > space group worked and yielded nice data with reasonable Rsyms, I/sig etc. > > When I then, though, re-enter the cell parameters etc (cp GXPARM.XDS > XPARM.XDS) and just run INTEGRATE and CORRECT, the cell parameters won't > refine any further, they stay right at the value given by XPARM.XDS. As Kay > suggested, no cell parameter refinement in cubic (cI)? > > Cheers > Jan > > > > On Oct 8, 2009, at 12:28 AM, Graeme Winter wrote: > >> Hi Jan, >> >> Always worth a try is to process the data in P1 then assigning the >> symmetry in CORRECT - that way the cell constants can refine to what >> they want to. It also means you can check that the symmetry actually >> is cubic. >> >> For the majority of data sets in my experience it makes little >> difference whether you assign the lattice constraints during >> integration, unless they're wrong. >> >> Cheers, >> >> Graeme >> >> >> >> 2009/10/8 Jan Abendroth <jan.abendr...@gmail.com>: >>> >>> Hi all, >>> I am running into a strange behaviour fo xds for a primitive cubic data >>> set. >>> Neither in the INTEGRATE nor in the CORRECT step the cell parameters are >>> refined and stay exactly at the value specified in XDS.INP. R-factors and >>> I/sigmas of the XSCALE run look suspiciously high/low. When I reduce the >>> symmetry to tetragonal and run an otherwise identical XDS.INP script, the >>> cell parameters are refined again. >>> Any ideas? >>> Thanks a bunch >>> Jan >>> -- >>> Jan Abendroth >>> deCODE biostructures >>> Seattle / Bainbridge Island WA, USA >>> work: JAbendroth_at_decode.is >>> home: Jan.Abendroth_at_gmail.com >>> >>> >>> >>> > > -- > Jan Abendroth > deCODE biostructures > Seattle / Bainbridge Island WA, USA > work: JAbendroth_at_decode.is > home: Jan.Abendroth_at_gmail.com >
