ENUMERATION OF NONRIGID MOLECULES BY MEANS OF UNIT SUBDUCED CYCLE INDEXES

Unit subduced cycle indices (USCIs) are applied to the enumeration of isomers derived from a non-rigid parent molecule, the non-rigidity of which stems from bond-rotations. The parent is divided into a rigid skeleton of G-symmetry and mobile moieties of H-symmetries, where each mobile moiety is linked to a root that is a terminal vertex of the skeleton. In the first step, isomeric mobile moieties are enumerated with respect to the H-symmetry in terms of USCIs for H. Second, the mobile moieties counted are regarded as substituents on the vertices of the rigid skeleton. This formulation allows us to enumerate mobile isomers by means of USCIs for the G-symmetry. © 1990 Springer-Verlag.