Re: [ccp4bb] bigger size - > better diffraction?

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

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Subject: Re: bigger size - > better diffraction?
From: Elspeth Garman elspeth {- at -} BIOP {- dot -} OX {- dot -} AC {- dot -} UK
Date: 2007-04-04

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Subject: Re: cryo was:bigger size - > better diffraction?
From: Tommi Kajander tommi {- dot -} kajander {- at -} HELSINKI {- dot -} FI
Date: 2007-04-04

Subject: Re: bigger size - > better diffraction?
From: artem {- at -} XTALS {- dot -} ORG artem {- at -} XTALS {- dot -} ORG
Date: 2007-04-04

A small comment: crystals that do not diffract well at R.T. can still
diffract well when frozen. There are several reasons for this, including:

* poor stability of crystal once the drop is open to the air

* crystal has low tolerance for handling (capillary mount can be
challenging and cause more physical damage, especially if the
experimenter is rusty with capillary mounts)

* the effect of freezing - it has been known to cause transitions between
space groups etc.

* the effect of cryoprotectant (dehydration, and so forth)

So - even if your stuff doesn't diffract well in a capillary - it still
can be saved sometimes :) Or not.

Artem

> diffracts in general. It is true it may be a cryo problem, but if
> the non cryo protected crystals do not diffract then why would one
> expect the cryo protected one to.

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

Previous message:
Subject: Re: bigger size - > better diffraction?
From: Elspeth Garman elspeth {- at -} BIOP {- dot -} OX {- dot -} AC {- dot -} UK
Date: 2007-04-04

Next message:
Subject: Re: cryo was:bigger size - > better diffraction?
From: Tommi Kajander tommi {- dot -} kajander {- at -} HELSINKI {- dot -} FI
Date: 2007-04-04