First-principles investigation of the formation of Mn/Ag(100) surface alloy

Abstract

Abstract We present ab initio results for the interdifusion energy and the formation energy of Mn/Ag(100) surface, subsurface and bilayer surface alloy films. From these results we conclude that in contrast with the Mn/Cu(100) system, which favours the formation of the Cu(100)-c(2 × 3) Mn surface alloy, the lowest-energy configuration is a c(2 × 2) antiferromagnetic Mn monolayer located in the second atomic layer below the Ag(100) surface. Antiferromagnetic monolayers being located in deeper layers show a slightly higher energy. Depending on the growth conditions, we expect on the basis of these results that Mn atoms diffuse into subsurface layers and form small Mn clusters. Superposition of Mn monolayers and Ag(100)-c(2 × 2) Mn layers in the second layer or a superposition of the monolayer with c(2 × 2) bilayer alloys may be intermediate metastable configurations. Total energy results are based on the density functional theory in the local-spin-density approximation and are carried out using the full-pot...