[phenixbb] Refinement of a complex with a symmetric inhibitor lying on the axis of symmetry

Hi, I try to refine a crystal structure of a protein - inhibitor complex. The protein is a homodimer and the two molecules have a crystallographic symmetry. The space group is P6122. The symmetric inhibitor binds symmetrically to the protein so that I refine the half of it. The core of the inhibitor is a five-membered ring with a nitrogen lying directly on the axis of symmetry. I achieved to refine this by setting the occupancy to 1.0. And now, here is my problem: Two C atoms of this ring system are bound across the symmetry axis - how could I include this in the refinement? Is there any possibility to generate restraints to the other part of the inhibitor (of the symmetry equivalent)?? Thanks for your help in advance, Ina Ina Lindemann Philipps-Universität Marburg Pharmazeutische Chemie AG Klebe Marbacher Weg 6 35032 Marburg Tel.: 06421/2825908