We present results of calculations of activation energy barriers for several processes involving a diffusing atom around a step edge on the (111), (100), and (110) surfaces of Cu using the nudged elastic band method with interaction potentials based on the embedded atom method. In the presence of a neighboring step, the Ehrlich-Schwoebel barrier for an adatom to undergo jump or exchange at a step edge is found to be independent of the separation between the steps unless they are at two-atom width apart, in which case the barrier is larger than that for an isolated step. The influence of the local step geometry on diffusion energetics is also discussed.

• Received 9 August 2005

DOI:https://doi.org/10.1103/PhysRevB.73.125426