change of hand in I41

[Roman Hillig <roman.hillig@mpi-dortmund.mpg.de>]

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I am having problems changing the hand in I41. 

When I invert x,y,z to -x,-y,-z for a derivative with 2 sites,
statistics in VECREF and MLPHARE become much worse, whereas the
statistics are fine when I input just one (inverted) site instead of two
sites at the same time. So it seems as if the Difference Patterson Peaks
are still consistent for the selfpeaks of site 1 and 2, but as if the
crosspeaks have changed. 

        As I understood, to change the hand one has to change all heavy
atom sites from x,y,z to -x,-y,-z, and in some cases one has to change
the spacegroup to the enantiomorphic spacegroup. In P41 this would
amount to changing the spacegroup to P43. Here, there is no spacegroup
"I43". Do I have to change the origin instead? 

	I wonder whether anyone else has encountered the same problem in this
space group and can help me out. Also I would like to understand why one
has to change the origin if it is so.

Thanks,

Roman 
-- 
Roman Hillig
Max-Planck-Institut fuer molekulare Physiologie
Abteilung Strukturelle Biologie
44139 Dortmund, Germany