M. Kuchler et F. Rebentrost, EFFECT OF ADSORBATES ON 2ND-HARMONIC GENERATION AT SIMPLE METAL-SURFACES, Physical review letters, 71(16), 1993, pp. 2662-2665
The changes of the nonlinear optical response by single atoms adsorbed
on free-electron-like metal surfaces are calculated in the low-freque
ncy limit. Density-functional theory and an extension of the atom+jell
ium chemisorption model by Lang and Williams allowing for the presence
of an external static field is used. The results enable a detailed di
scussion of the mechanisms responsible for the characteristic effects
of adsorbates on second-harmonic generation as evident from recent exp
eriments on metal surfaces.