The wave functions and eigenenergies for lithium atom motion on a graphene were obtained by solving a Schrödinger equation for Li atom motion using the potential energy surface constructed in the framework of density functional theory calculations. The wave functions for Li atom motion showed that the diffusion barriers were lower than those predicted by the potential energy surface due to the quantum effects. The diffusion coefficients based on the transition state theory showed that the diffusion from one hollow site to another along the carbon-carbon bond axis was favored at high temperature, compared to that via the mid-point of carbon-carbon bond.

Quantum States and Diffusion of Lithium Atom Motion on a Graphene. Kubota, Y., Ozawa, N., Nakanishi, H., Kasai, H.: Journal of the Physical Society of Japan, 2010, 79[1], 014601