The diffusion dynamics of Li+ ions on fullerene were investigated using the direct molecular orbital method. The total energy and energy gradient on the full dimensional potential energy surface of the Li+C60 system were calculated at each time-step in the trajectory calculation. The optimized structure, where the Li+ ion was located at the hexagonal site of C60, was used as the initial structure at time zero. Simulation temperatures between 10 and 300K were chosen. The dynamics calculations showed that the Li+ ion vibrated around the initial equilibrium point below 40K, while the ion could move above 50K. Below 300K, the diffusion coefficients for the Li+ ion on the present surfaces were larger than those for a graphite surface. The diffusion coefficients on both C60 and graphite surfaces were almost equivalent at about 300K. Above 300K, the coefficients for the graphite surface were significantly larger than those for C60.

Diffusion Dynamics of the Li Ion on C60: a Direct Molecular Orbital - Molecular Dynamics Study. Tachikawa, H.: Journal of Physical Chemistry C, 2007, 111[35], 13087-91