Re: [ccp4bb] Twinning: P43 apparently P42212

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CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

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From: Bernhard Rupp bernhardrupp {- at -} SBCGLOBAL {- dot -} NET
Date: 2007-10-06

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Subject: Re: Twinning: P43 apparently P42212
From: Charlie Bond Charles {- dot -} Bond {- at -} UWA {- dot -} EDU {- dot -} AU
Date: 2007-10-07

Hi Folks,

Thanks for the many useful responses. The answer to the conundrum is
indeed as some people suggested .... P212121 with a=b and twin operation
kh-1.

This is a very high-resolution dataset and I am using shelxl to refine
which allows inclusion of twinning (as does phenix.refine btw). If I'd
looked beyond the obvious in the shelx manual I would have found my
situation as the second "Frequently encountered twin law".

Getting to this answer was confounded by the arrangement of molecules
allowing quite reasonable refinement with some dual conformations in
P43212 (with half as many atoms per au).

Cheers,
Charlie

--
Charlie Bond
Professorial Fellow
University of Western Australia
School of Biomedical, Biomolecular and Chemical Sciences
M310
35 Stirling Highway
Crawley WA 6009
Australia
Charles.Bond@uwa.edu.au
+61 8 6488 4406

CCP4bb navigation

CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: example for map averaging?
From: Bernhard Rupp bernhardrupp {- at -} SBCGLOBAL {- dot -} NET
Date: 2007-10-06