[phenixbb] peptide ligand refinement problems

Dear Phenix Users, My colleague has got into trouble when he was refining a peptide ligand with a coumarin ring attached via a peptide bond. The peptide part is composed of natural amino acids, which does not require a cif file. On the other hand, a cif file has been created for the coumarin ring. Unfortuantely, after the refinement run, the peptide and the coumarin ring fell apart, and we could not figure out why this is happening. We are using the Phenix-dev-1370 version. Any help would be appreciated! Thank you in advance, Mengbin -- Mengbin Chen Department of Chemistry University of Pennsylvania