We examined the densities of states projected on the various atoms involved in the binding process (PDOS). Some representative PDOS curves are shown in Figure . Comparisons of unbound and bound PDOS indicate the shifts in the energies of orbitals that have density on a specific atom or group of atoms, as a result of the binding process. In general, for a bare surface, the surface-atom PDOS depends on the site's CN and not on the number of adatoms present on the surface. PDOS calculated for sites with the same CN completely overlap those shown in the top of Figure