Quantum size effects in metallic overlayer epitaxy

Ab-initio total energy calculations have been performed to study the stabil ity and electronic structure of epitaxial Sb and close-packed Ag films on G aAs(110) surfaces. These are model metal-semiconductor systems that have be en studied extensively experimentally. The method used is density functiona l theory within the pseudopotential approximation. These calculations provi de information on the relaxation and structure of the Sb and Ag surface lay ers and the stability of the metal films as a function of the number of met al layers.