Effect of Au Adsorption on the Tungsten (100) Surface State

The peak at ${\epsilon }_{\mathrm{F}}-0.3\mathrm{}$ eV seen in field-emission energy distributions for the (100) plane, which is quenched by H, O, and Kr, is not quenched by Au adsorption up to slightly above monolayer coverages. The peak does disappear abruptly at $\frac{\mathrm{Au}}{\mathrm{W}}>~1.15$ where a spontaneous rearrangement of Au out of the W lattice sites seems to occur. This suggests a surface resonance which can be transferred to the outermost layer, even if this is not W, as long as the potertial seen by the bulk electrons is sufficiently tungstenlike.