Yes, good point Eleanor! Many people seem to be under the misapprehension that SRFs show only peaks due to _local_ NCS, but of course they are indifferent to the kind of symmetry relationship and will show all relationships (both crystallographic and NCS) within the specified radius of integration, including as you say A -> B_symN etc. which usually do not form a closed NCS point group as A -> B -> C etc. usually do. I find that it can be useful when analysing an SRF to also check these non-local NCS symmetry peaks.
Greetings! -- Ian On Mon, 11 Jun 2018 at 10:41, Eleanor Dodson < [email protected]> wrote: > Hmm - PISA first to make the most likely assembly. of A B C D etc.. > > Then GESAMT to match A to B , A to C ,. ... B to C , etc > That gives "self rotations" in polar (most useful) , Euler, and matrix.. > > That could all be scripted - Eugene? > > But of course self rotation lists do not necessarily give the most > informative result - they might well report A to B_symN > > E > > > > > On 11 June 2018 at 09:53, Randy Read <[email protected]> wrote: > >> Hi, >> >> I'd prefer not to have to reinvent a wheel that I'm almost certain is >> already out there! Is there a nice tool for taking a set of coordinates >> and space group information, working out the NCS relationships, applying >> symmetry and generating a list of peaks that should be expected on a >> self-rotation function? Something that takes a list of NCS operators >> instead of coordinates would also be okay, though slightly less >> convenient. I've seen annotated self-rotation functions in papers, but I'm >> failing to find anything in the list of CCP4 programs that would do this. >> >> Computing a self-rotation function from the Fcalcs is another option to >> prove that the structure agrees with the self-rotation function computed >> from the data, but it would sometimes be helpful to be able to say which >> pair of molecules led to a particular peak. >> >> Thanks! >> >> Randy Read >> >> ------ >> Randy J. Read >> Department of Haematology, University of Cambridge >> Cambridge Institute for Medical Research Tel: + 44 1223 336500 >> Wellcome Trust/MRC Building Fax: + 44 1223 336827 >> Hills Road E-mail: [email protected] >> Cambridge CB2 0XY, U.K. >> www-structmed.cimr.cam.ac.uk >> >> ######################################################################## >> >> To unsubscribe from the CCP4BB list, click the following link: >> https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1 >> > > > ------------------------------ > > To unsubscribe from the CCP4BB list, click the following link: > https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1 > ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1
