Surface segregation and surface electronic structure of PtCu alloys: Dependence on atomic coordination

Abstract

Ultraviolet photoemission experiments have been performed on the (110) and (111) single crystalsurfaces of PtCu alloy. The difference in their surface atomic arrangements gives rise to different peak shapes in the Cu 3d‐derived surface ’’density of states’’. The PtCu (110) sample, with 1.9–2.3 at. % Cu in the bulk, shows 5.6%–7.7% Cu near the surface. The PtCu(111) sample, in comparison, shows insignificant Cusurface segregation.