Three Isolated-Pentagon-Rule Isomers of C96 Fullerene Isolated as Trifluoromethyl Derivatives.

The family of experimentally confirmed isolated-pentagon-rule (IPR) isomers of C96 fullerene is extended by trifluoromethylation of a C96 fraction of the fullerene soot, high-performance liquid chromatography separation of CF3 derivatives, and a single-crystal X-ray diffraction study of C96(CF3)n compounds with the use of synchrotron radiation. New cage isomers were revealed in C96(94)(CF3)18/20 and C96(182)(CF3)18 compounds, whereas isomer C96(181), previously known in the adduct with nickel porphyrinate, was confirmed in C96(181)(CF3)18/20 derivatives. Common and special features of the addition patterns of CF3 groups on C96 carbon cages are discussed in more detail. The investigated isomers belong to the most stable C2-C96(181) and slightly less stable C1-C96(94) and C2-C96(182) among the altogether 15 experimentally confirmed IPR isomers of C96 fullerene.