Lattice dynamics of fullerene C60 crystals

Using versatile atom-atom potentials obtained from the properties of hydrocarbons and graphite crystals, the density of intermolecular vibrations and lattice specific heat of low-temperature phase of fullerene C60 crystal have been calculated. On the basis of experimental data analysis and results of the calculations the two-orientation model of C60 crystal disordering has been confirmed: the near order with molecule orientation 21 deg is manifested as IR absorption band at 10 cm-1, while is case 73 deg orientation - in the form of IR absorption band at 20 cm-1 and a narrow intensive peak in the spectrum of neutron inelastic scattering at 22 cm-1. 35 refs., 4 figs