PNNL

Abstract

The Cu overlayer adsorbed on CaO(100) was studied at the density functional level of theory. Following an experimental suggestion, we examined a complete c(1X1) structure with copper atoms adsorbed on every hollow site of CaO(100). The binding energy/atom for this structure is 3.19 eV. However, another c(1X1) structure proposed by us, with copper atoms on every surface Ca and O atoms, displayed a larger binding energy of 3.37 eV. When the copper coverage is reduced by half, the preferred adsorption site fo rhte Cu overlayer is above the O site and the dominant mechanism for the metal adhesion is rehybridization of the metal 3d and surface O 2p bands. Our results suggest a delicate balance between the formation of a monolayer film and 3D particles on the substrate.