Properties of the surface diffusion of sulfur on nickel and the effects of surface defects

Abstract
The surface diffusion of sulfur on Ni and the influences of surface defects are studied. Our calculated results show that the activation energies on Ni(100) and Ni(110) are much larger than on the Ni(111) plane. A Ni adatom on Ni(111) is a trap, but a vacancy is a high potential barrier for the diffusing sulfur atoms. A step will greatly increase the activation energy when a sulfur atom diffuses across it.