The adhesion nature of the Ag/MgO(100) interface: An ab initio study

The atomic and electronic structure of the Ag/MgO(100) interface are calculated by means of the ab initio Hartree-Fock approach combined with a supercell model. The electronic density distribution and the interface binding energy/distance are analyzed for different Ag adsorption positions, slabs of different thicknesses and varying Ag surface coverage. It is demonstrated that the adhesion energy arises mainly due to the electrostatic interaction of substrate atoms with a complicated charge redistribution in the metal layer(s), characterized by large quadrupole moments as well as electron density redistribution towards bridge and hollow positions between the nearest and next-nearest Ag atoms.