ELECTRONIC-PROPERTIES OF A MONOLAYER OF THALLIUM DEPOSITED ON AG(111)

The density functional formalism is used to investigate theoretically the underpotential adsorption of Tl on Ag(111). In agreement with expe riment, a relatively compact structure is predicted for the adsorbed m onolayer. While the work function of the substrate covered by a monola yer of adsorbate is very close to that of the pure adsorbate metal, th e position of the effective image charge differs appreciably for both systems. The second harmonic generation response of the system is also analyzed in the quasi-static limit.