Results concerning the diffusion of O2- adatoms on the NiO(001) surface obtained were obtained by means of molecular dynamics simulations that were based upon a rigid-ion potential model. The homologous temperature range of 0.37 to 0.71 was covered. It was found that the energetically favored adatom position was located at the hollow site of the Ni sub-lattice. From the detailed analysis of the ionic trajectories, it was found that the adatom diffuses via simple hopping and multiple exchange mechanisms. All processes exhibited Arrhenius behaviour, from which the corresponding migration energies were deduced. It was also found that, although the frequency rates for hopping and exchange were comparable, the contribution of the latter to the total diffusion coefficient was more important than that of hopping; by as much as an order of magnitude at high temperatures.

Oxygen Adatom Diffusion on the NiO(001) Surface by Molecular Dynamics Simulation. D.G.Papageorgiou, T.Karakasidis, G.A.Evangelakis: Physica B, 2002, 318[2-3], 211-6