Variable charge molecular dynamics was performed in order to study the diffusion mechanisms of oxygen atoms in nickel at 950 to 1600K. It was observed that oxygen did not diffuse via jumps of oxygen through interstitial sites but via a vacancy diffusion mechanism. The oxygen diffusivity could be well described by an Arrhenius law over the temperature range considered. The oxygen diffusion coefficient was analysed and indicated a relationship of the form:

D(cm2/s) = 3.92 x 101exp[-1.99(eV)/kT]

The numerical results were compared with a compilation of experimental and theoretical studies, and exhibited good agreement with previous approaches.

Diffusion of Oxygen in Nickel: a Variable Charge Molecular Dynamics Study. Garruchet, S., Politano, O., Arnoux, P., Vignal, V.: Solid State Communications, 2010, 150[9-10], 439-42