Low frequency Raman active vibrations in fullerenes. 1. Monopolar modes

Raman measurements and PM3 calculations of low frequency (<600 cm(-)) vibra tional modes in a variety of different, fullerenes can be rationalized in t erms of the multipolar "acoustic'' oscillations of isotropic spherical and spheroidal shells. In this first of a two part series, we show that all ful lerene cages have monopolar-like breathing vibrations. Within certain bound ary conditions and in the absence of other data, the frequency of these vib rations may be used for cage size determination.