Hi Carsten,
is this concept expandable to refining two or more ligands with different resnames and atomnames on top of each other in the same physical location using altlocs?
yes. An example in PDB is: http://www.rcsb.org/pdb/files/1EJG.pdb where residues #22 will be treated ok in phenix.refine automatically.
I vaguely recall that phenix supports this approach but have not tested it out myself yet.
I implemented this more than a year ago right after Ralf made it possible to get occupancy groupings as part of PDB interpretation.
Hypothetical case in point: 3 Ligands with resnames LG1, LG2 and LG3, differing atomnames, all chain C and resi 1, altlocs from A to C. Is something like this supported? What kind of requirements would I need in order to do this?
I'm not sure I understood this after spending 2 seconds looking at it, but if you send me an example PDB file and tell what is supposed to be coupled with what, then I will send you an example. (I'm leaving for Zürich right now and hopefully will be able to reply tonight). Pavel.