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Re: [ccp4bb]: need estimated error of occupancy



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Hi Susan,

have a look at the peak heights in the anomalous difference electron
density map. Even far from any absorption edge you often have a 
significant anomalous signal. Calibrate it against the sulfur peak
heights, then you may be able to get a decent estimate of the 
occupancy of your ions.

-Manfred.


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On Tue, 21 May 2002, Susan Heffron wrote:

> ***  For details on how to be removed from this list visit the  ***
> ***          CCP4 home page http://www.ccp4.ac.uk         ***
> 
> Hi all.
> 
> We are looking for a method to calculate the "estimated error" for the
> occupancy values of the ions in our protein structure.  The occupancy
> was refined in X-PLOR or CNS.  A reviewer of our paper is requiring an
> "estimated error" of these values.  All suggestions for how to calculate
> this are appreciated.
> 
>                          Sincerely,
>                          Susan
> 
> -- 
> ------------------------------------------------------------------
>         Susan Heffron
> Dept. of Physiology and Biophysics                               
> University of California, Irvine                
>  Irvine, CA  92697-4560   U.S.A.                         
>     phone:  (949) 824-4625
>     FAX:    (949) 824-8540
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>