Hi Igor, yes, it is possible to do this in phenix.refine. There are several ways of doing this that are described here: http://www.phenix-online.org/documentation/reference/refinement.html#occupan... Also, you can send me PDB file and I will make sure things work as desired. Pavel On 9/18/14 1:30 PM, Igor Petrik wrote:

Hi,

I am trying to refine a structure in which there are two sets of linked conformations of two residues. Around half of the occupancy (altloc A) corresponds to the sidechain of residue 29 pointing into the pocket and residue 65 pointing out and the other conformation (altloc B) has the side chain of residue 65 in the pocket (where residue 29 is in altloc A) and residue 29 pointing out of the pocket. I am refining them by using occupancy refinement groups in, but phenix refine seems to think that altloc A of residue 29 and altloc B of residue 65 may exist at the same time and pushes them apart to avoid clashes. Is there any way around this?

- Igor