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 <[log in to unmask]>:
>> 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
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