AN INTERATOMIC POTENTIAL FOR FULLERENES FROM THEIR VIBRATIONAL-SPECTRUM

The vibrational analysis of sp2-bonded carbon clusters with different nearest-neighbour interatomic distances, (2 in C60, 8 in C70), performed in the framework of the bond-charge model, leads to the determination of an exponential form for the short-range interatomic potential which is inclusive of charge transfer effects. The potential, besides leading to excellent agreement with the existing spectroscopic data and ab initio Car-Parrinello calculations, ensures a good transferability of the model to other clusters and possibly an empirical basis for molecular dynamics simulations.