Re: [ccp4bb] cns and refmac refinement

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Subject: Re: cns and refmac refinement
From: Lijun Liu liulj {- at -} UOXRAY {- dot -} UOREGON {- dot -} EDU
Date: 2008-02-21

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Subject: Re: cns and refmac refinement
From: William Scott wgscott {- at -} CHEMISTRY {- dot -} UCSC {- dot -} EDU
Date: 2008-02-21

Subject: Re: cns and refmac refinement
From: Anastassis Perrakis a {- dot -} perrakis {- at -} NKI {- dot -} NL
Date: 2008-02-21

Just to point out that I have missed the NCS presence; Lijun is
*perfectly* correct; even more I should emphasize the point and
say that at 3.0 A, Thou Must Use NCS (if I say again anything about
Gospels and Kleywegt we end up with more facebook groups ...)

> I think there is no reason at this resolution edge (~3A), making
> bonds possibly resolvable, that NCS should not be used,

>> By the way, it is a dimer and I didnot use NCS restarin
>> during refinement. Below is from refmac log:

I would however disagree with Lijun thats its instability. Of course
the 180 cycles are of no use at all
(10 cycles in Refmac are more than enough in 99% of cases), but Rfree
shoots up from 32.6 to 36.2 in 12 cycles,
which is clearly an indication of some sort of pathology, and not
instability.

Well, tight NCS is the best starting point in this case.

Tassos

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CCP4bb <-- 2008 <-- February 2008 <-- 21 February 2008

Previous message:
Subject: Re: cns and refmac refinement
From: Lijun Liu liulj {- at -} UOXRAY {- dot -} UOREGON {- dot -} EDU
Date: 2008-02-21

Next message:
Subject: Re: cns and refmac refinement
From: William Scott wgscott {- at -} CHEMISTRY {- dot -} UCSC {- dot -} EDU
Date: 2008-02-21