▎ 摘　　要

The interactions, of magnesium species (Mg, Mg+, and Mg2+) with a graphene surface have been investigated by the density functional theory (OFT) method. The distances of Mg atoms from the graphene surface were calculated to be 1.80 angstrom (Mg2+), 2.16 angstrom (Mg+), and 4.17 angstrom (Mg) at the Coulomb-attenuating method (CAM)-B3LYP/6-31G(d) level. The binding nature of Mg ions (Mg2+ and Mg+) is caused by the charge transfer interaction; and the Mg atom interacts with the surface via van der Weals (vdW) force. The Mg ions can diffuse via the C-C bond center between hexagonal sites. The barrier heights for the diffusion of Mg2+ and Mg+ on the graphene surface were calculated to be 14.6 and 2.8 kcal/mol, respectively. On the other hand, the diffusion of Mg atoms proceeds with a very low barrier. The mechanism of the interaction of Mg with the graphene surface was discussed on the basis of theoretical results. (C) 2014 The Japan Society of Applied Physics