  We report a computational study of the anharmonicity of the vibrational modes
of various individual fullerenes using the "moments method" [Y. Gao and M. Daw,
Modelling Simul. Mater. Sci. Eng. 23 045002 (2015)] with a Tersoff-style
potential for carbon. We find that the frequencies of all vibrational modes
drop systematically with temperature and the sizes of the individual fullerenes
do not affect strongly the anharmonicity of the modes. Comparison is made with
available experiments.
