Electronic Structure of Fullerene C60 and C70

Among the properties of fullerenes that can be related to their electronic structure and their symmetry, the optical properties are of particular relevance in view of the potential applications that might be based on them, such as the production of fullerene-based optical limiters. In this contribution we review the optical properties of the two most abundant fullerenes, C60 and C70 by focusing on electronic spectroscopy studies carried out in solution, noble gas matrices or in the gas phase, in other words in conditions where the properties of approximately isolated molecules can be monitored. These spectroscopic studies represent an important source of information about the effect of intramolecular couplings, although the interactions with the solvent will also cause significant with the results of quantumchemical computational studies carried out on isolated fullerene molecules perturbations that appear in the spectra. On the other hand, these spectroscopic data are directly comparable.