library Topology and parameter files topology Topology and parameter files residue Topology and parameter files compatibility Topology and parameter files standard Topology and parameter files X-PLOR Using available X-PLOR topology files conversion Converting XPLOR topology files to MAIN form residue Modifying and creating new topology library entries nonstandard Modifying and creating new topology library entries residue Create a new entry from atom coordinates entry Create a new entry from atom coordinates new topology Create a new entry from atom coordinates