molecular replacement non-standard symmetry

[Yu Wai Chen <ywc@mrc-lmb.cam.ac.uk>]

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Dear all,

I have collected data that shows 4/mmm.  I also see h=2n (and k=2n)
absences.  I am missing data on the l axis.  To play safe, I processed
the data in P4212 (90) and tried to do molecular replacement in all the
allowed space groups:

  P4212(90), P41212(92), P42212(94) and P43212(96)

I could not find an obvious solution.

My colleague told me that one needs to try "non-standard" space groups
as well.  Does it mean I also need to do something like:

  P4221, P41221, P42221 and P43221?

If yes, where (or how) can I find out the symmetry operations for these
non-standard groups?

Thank you very much.

Wai
-- 
===================================================================
Yu Wai CHEN, Ph.D. ..................   email:ywc@mrc-lmb.cam.ac.uk
 Centre for Protein Engineering,             tel:+44-(0)1223-402148
 MRC Centre, Hills Rd, Cambridge CB2 2QH, UK fax:+44-(0)1223-402140
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