Theoretical studies on the structure and electronic spectra of some isomeric fullerene derivatives C60On (n=2, 3)

Possible isomers of Buckminsterfullerene derivatives C60O2 and C60O3 are studied with the semiempirical quantum mechanical INDO method. The C60O2 isomer of Cs symmetry, where the epoxy oxygen atoms are on the 6–6 bond of a hexagon, is found most stable. The C60O3 isomer of C3v symmetry with a single epoxy chain connecting both carbons of a 6–6 bond is most stable. However, the other two isomers of C2 and Cs symmetries are near as stable. In all cases, the 6–6 carbon–carbon bond in the epoxial ring is not broken. Based on the structures so identified, the calculated electronic spectra of C60O2, and the 13C-NMR analysis of both C60O2 and C60O3 agree well with experiment. The calculated electronic spectra of C60O3 are theoretical prediction. The chemical reactivity of C60O2 and C60O3 is discussed in connection with our calculated results.