Hi, I am trying to do a refinement with phenix.real_space_refine (RSR) on an EM map with a protein and a known ligand (NAG is the monomer code). In the pdb file supplied the C1 atom in the NAG molecule is positioned nicely in the EM density at a distance of 1.38Å from a ND2 atom in an ASN residue of the protein. The O1 atom in the NAG molecule is not present suggesting there should be a covalent bond here I believe. Both ASN and the NAG molecule have the same chainID. The problem is that RSR moves the sugar away even though I have used command line options such as pdb_interpretation.automatic_linking.link_carbohydrates=True or even pdb_interpretation.automatic_linking.link_all=True. The atoms end up at an un-bonded distance of 2.85Å from each other after refinement to the point that one of them is poking out of the density. Are my phil parameters incorrect? I noticed that I don't get an error message if I misspell say pdb_interpretation.automatic_linking.link_carbohydrates to pdb_interpretation.automatic_linking.link_carbohydrate. RSR still runs to completion so I'm wondering if it actually interprets the PHIL parameter at all. Another peculiarity is that the log file comments that NAG is an unusual residue rather than stating it is a well-known carbohydrate. If anyone on here knows how to compel phenix RSR into creating automatic links to carbohydrates suggestions would be much appreciated. Many thanks, Rob