Comparison of an experimental and a theoretical study of the surface alloy Pt/Cu(111)

Abstract Electron spectroscopies have been used to characterise the surface alloy formed by annealing a nearly epitaxial thin film of Pt/Cu(111). The surface alloy extends over several monolayers and is the result of a non-classical dissolution of Pt into the Cu substrate. The surface layer composition is Cu 3 Pt reminiscent of the L1 2 alloy phase. In the bulk alloy this phase may be modelled using first neighbour effective pair interactions. This model is extended to the dissolution of a thin film of Pt into the Cu(111) substrate, by making use of the concept of local equilibrium. We show that at low temperature we can indeed stabilise an L1 2 surface alloy phase.