Energy barriers for diffusion on stepped Pt(111) surface

We performed molecular statics calculations of energy barriers for adatom m oves in the vicinity of steps on Pt(1 1 1) surface. We used the semi-empiri cal many-body Rosato-Guillope-Legrand potential and we systematically calcu lated barriers for descent of straight steps, steps with a kink and small i slands as well as barriers for diffusion along the step edges. We confirmed that the lowest barrier for descent is for an exchange process near kink's or island's corner on a step with a {1 1 1} microfacet. Diffusion along a step with a {1 1 1} microfacet is faster than along a step with a {1 0 0} m icrofacet. We also calculated barriers for diffusion on several surfaces vi cinal to Pt(1 1 1). Our results are compared with previous calculations. (C ) 1999 Elsevier Science Ltd. All rights reserved.