Superdiatomics and Picosprings: Cage-Cage Vibrations in C_(120)O, C_(120)O_2, and in Three Isomers of C_(130)O

摘要

The title compounds comprising furanoid- (C_(120)O, C_(130)O) or bisfuranoid-linked (C_(120)O_2) fullerene cages were prepared from C_(60)O and C_(60)/C_(70). For C_(130)O, three isomers were isolated. Following HPLC separation all substances were characterized as (microcrystalline) solids by Raman spectroscopy. Measurements, which in the case of C_(120)O and C_(120)O_2 commenced at Stokes shifts greater than 15 cm~(-1), were interpreted in terms of semiempirical calculations (MP3) both of ground-state energetics as well as of vibrational frequencies. Good agreement between (harmonic) vibrational frequency predictions and Raman spectra was obtained. A comprehensive discussion of low-frequency cage-cage vibrations in fullerene dimers and related compounds is attempted on this basis.