Dynamic effects of surface plasmons on the lifetimes of neutral excited rare-gas atoms physisorbed on metal surfaces

Abstract

Numerical calculations are presented for the optical spectra of neutral rare-gas atoms physisorbed on metal surfaces. The excitation spectra of adsorbates on metal surfaces have been calculated at low coverage and when the nonradiative processes due to the damping of the surface plasmons dominate. Numerical results indicate that the peaks of the symmetric and antisymmetric modes arising from two nearby excited states of the physisorbed atom on the metal surface cancel each other out provided that the frequency profiles of the peaks in question overlap. The resulting excited geometrical configurations arising from the cancellation process between the spectra of the symmetric and antisymmetric modes have been computed as a function of the distance R from the atom to the metal surface, and they are presented graphically. The vanishing computed spectra of Xe and Al and Au and the persistence of the spectra of Xe on Mg, Cu and Ar on Au and Mg are compatible with experimental observations. Predictions have been...