[ccp4bb]: Multicrystal Averaging?

[Yong Xiong <yxiong@chemistry.ohio-state.edu>]

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Dear all, 

We have a RNA molecule grew in a number of diffrent space groups (6 or
7). We collected a Br MAD data set on one of the crystal forms. Some how
all of the resolution shells have very close Rsym values (relatively
high, ~8% throughout). We managed to get the Br positions and the initial
phases. The map was interpretable but not very clear. We would like to try
the multicrystal averaging to improve the phases. Please someone give us
some help on how to do this? Some command files would be great
helps. Also, how can we identify whether the molecular structures are
really close in diffrent space groups?

In addition, we do have a native data set. What is the best way to put it
together with the MAD set in MLPHARE for phasing? Do we just set the
native as the the native set and the 3 wavelengthes as derivatives?

Thanks in advance!

Yong