First-principles calculation of ZnS monolayer on Cu(111) surface

Abstract

First-principles calculation is carried out on the interface of the ZnS(001) monolayer and Cu(111) surface. It is found that the ZnS monolayer significantly reconstructs after geometry optimization. The out-of-plane S atom has a positive displacement in the z direction while other atoms (Zn and S) have small displacements on the ZnS monolayer. The interface stacking sequence has an influence on the flatness of the ZnS monolayer and the binding energy of the interface. There are two approaches for the ZnS monolayer to reach the lowest energy state which take place on the two kinds of S atoms in the ZnS monolayer and result in the bulging feature. The van der Waals (vdW) interaction exists between ZnS monolayer and Cu surface.