Variations in the Nature of Metal Adsorption on Ultrathin Al(2)O(3) Films;Physical Review Letters

摘要

First-principles density-functional calculations are used to study metal adsorption (Li, K, Y, Nb, Ru, Pd, Pt, Cu, Ag, Au, and Al at 1/3-4 monolayer coverages) atop 5; A1203 films on Al(Ill). The oxide-metal bond is ionic at Iow coverages but, with interesting exceptions, caused by polari received at high coverages where the overlayer is metallic. Binding trends are explained in terms of simple concepts. Increasing overlayer thickness can cause the adsorbate-oxide interface structure to than . %lEc o; 1998 and while some metals wet, most do not.