Structures of a Ag monolayer deposited on Cu(111), Cu(100), and Cu(110) substrates: An extended tight-binding quenched-molecular-dynamics study

We determine the atomic structure of a Ag monolayer deposited on the three low-index faces of a Cu substrate by means of an extended tight-binding quenched-molecular-dynamics simulation. For the (111) face, the most stable structure is a p(10×{}10) one. The surface plane is strongly waving, the perturbation extending up to the first ten surface layers. For the (100) face, the pseudohexagonal reconstruction c(10×{}2) is stabilized with respect to pseudomorphy and pseudoepitaxy. The case of the (110) face is more intricate. As a function of the Ag coverage, we predict a sequence of superstructures going from the p(2×{}7) missing-row reconstruction at low coverage up to the pseudohexagonal p(7×{}2) reconstruction at the monolayer completion.