Ab initio density-functional calculations were performed to investigate the surface properties of Cu(111) and Li diffusion in Cu thin films. The calculation results including lattice constant, cohesive energy, work function and surface energy were in fair agreement with that derived from corresponding experiments. The various diffusion pathways such as diffusion of Li as a substitution atom and various mechanisms were investigated using ab initio molecular dynamics. The energy barrier was calculated corresponding to each possible pathway. Theoretically, it was shown that Li could diffuse through Cu thin films by successive nearest-neighbor vacancy-atom exchanges. Therefore, nearest-neighbor vacancy-assisted jumping was deduced to be the most probable upon comparing the various mechanisms. It was found that more free diffusion could be observed by increasing the number of Cu vacancies in the thin film. It was also confirmed that diffusion was more marked as the temperature was increased.

Ab initio Investigation of the Surface Properties of Cu(111) and Li Diffusion in Cu Thin Film. Z.Xiong, S.Shi, C.Ouyang, M.Lei, L.Hu, Y.Ji, Z.Wang, L.Chen: Physics Letters A, 2005, 337[3], 247-55