Energetics, bonding mechanism, and electronic structure of metal-ceramic interfaces: Ag/MgO(001)

Electronic-structure total-energy investigations for the metal-ceramic interface system Ag/MgO(001) show that the preferred adsorption site for the overlayer Ag atom is above the O site of the clean MgO(001) surface. The binding energy of the overlayer Ag atom on the MgO(001) surface is 0.3 eV/atom (0.64 J/m2). No significant charge transfer is found between the overlayer Ag and the MgO(001) substrate, and the interface effect on the MgO(001) substrate is limited to the interface layer. The Ag overlayer shows typical metal features in the electronic band structure as well as in the charge distributions. The interface O atom is slightly metallized, i.e., the occupied states at the Fermi energy have hybridized O-Ag character. Compared with the O, the Mg is less influenced by the Ag.