Enumeration of chiral and positional isomers of substituted fullerene cages (C20-C70)

Abstract

Enumeration of chiral isomers of substituted fullerene cages (C[sub 20]-C[sub 70]) is considered using the generalized character cycle index (GCCI) of the alternating representation of the point group of the parent cage. It is shown that there are no chiral isomers for the monsubstituted C[sub 20], C[sub 24], C[sub 28], C[sub 30], C[sub 36], and C[sub 60] fullerene cages but there are chiral isomers for other monosubstituted cages. All cages considered here possess chiral isomers for disubstituted cages. It is shown that the number of positional isomers can be obtained using the GCCI of the totally symmetric representation. We also enumerate the [sup 13]C NMR signals of all fullerene cages C[sub 20]-C[sub 70]. 30 refs., 4 figs., 6 tabs.