It was recalled that an isolated adatom, adsorbed onto the surface of a current-carrying metal, felt a wind force; plus changes in the surface resistivity. By using the jellium model, it was found possible to derive a simple relationship between the wind force and the change in surface resistivity which was caused by the adatom. The relationship arose because both of the quantities had a common physical cause. That is, an exchange of momentum between the adatom and the carriers which impinged upon the surface from the interior of the metal. A layer-type Korringa-Kohn-Rostoker calculation was used to study the relationship between the electromigration wind force and the surface resistivity which was induced by an isolated Ag adatom on Ag(111). Unlike all previous studies of adatom electromigration on surfaces, the present approach permitted the calculation of the wind forces which were felt by both the adatom, and by atoms within the substrate. It was shown that the presence of the adatom significantly altered the magnitude of the wind force which was exerted on substrate atoms that were close to the adatom adsorption site. This information was used to study how the momentum transfer at the surface was partitioned between the adatom and the substrate atoms. It was shown that this effect significantly altered the relationship, between wind-force and surface resistivity, which was deduced from jellium models for the substrate.

Relationship between Adatom-Induced Surface Resistivity and the Wind Force for Adatom Electromigration - a Layer Korringa-Kohn-Rostoker Study. M.F.G.Hedouin, P.J.Rous: Physical Review B, 2000, 62[12], 8473-7