[ccp4bb] Twinning

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

Previous message:
Subject: Re: Rfree going up
From: Eleanor Dodson ccp4 {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2009-08-03

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Subject: Re: Twinning
From: Matthew Franklin Matthew {- dot -} Franklin {- at -} IMCLONE {- dot -} COM
Date: 2009-08-03

Subject: Twinning
From: Rana Refaey dr_rr81 {- at -} HOTMAIL {- dot -} COM
Date: 2009-08-03

Hi all,
I have a few datasets that I think are twinned for several reasons.
1)The Rfree and Rmerge are both stuck very high.
2) The L-test for twinning in Scala shows twinning
3) Also the centric and acentric movements suggest twinning.
4) The spots do not match the predication from Mosflm (Non-merohedral
twinning ?)

The space group is p212121, and am able to solve the structure using MR. But
when its comes to refining the Rfact and Rfree are stuck at high values (for
one of them at a resolution of 1.65 A they are 0.32 and 0.36 respectively )

Any suggestions how i could deal with these datasets ?

Many thanks

Rana

CCP4bb navigation

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

Previous message:
Subject: Re: Rfree going up
From: Eleanor Dodson ccp4 {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2009-08-03

Next message:
Subject: Re: Twinning
From: Matthew Franklin Matthew {- dot -} Franklin {- at -} IMCLONE {- dot -} COM
Date: 2009-08-03