Re: [ccp4bb]: Questions about translational NCS

[Gregory Verdon <g.verdon@chem.rug.nl>]

Hi,

I don't know what you mean with pure translational NCS.

Yes, you will see it if you calculate a self-patterson (you should see one or several

big peaks depending notably on the number of molecules).

My guess would be that a translational NCS (with only one translational element, along an axis) is never completely

parallel to a crystallographic axis since the molecules related by the NCS

are not strictly identical and thus are most probably not oriented in the same way relative to the

cell axis. If it is parallel, then it should be part of the crystallographic symmetry and the a.u

and the cell would be smaller. I am not absolutely sure about that. May be a symmetry master

can clarify that point !?!?

Looking forward to hear from someone, who knows !!!

 

                        Greg

 
  ________________________________________________________________
                                                                
  Gregory Verdon                                                                                                                                   
  Laboratory of Biophysical Chemistry                                     
  Department of Chemistry                                                  
  University of Groningen                                                  
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