Adsorbate-substrate vibrational coupling in physisorbed Kr films on Pt(111)

Abstract
Surface-phonon dispersion curves have been measured by inelastic He scattering for thin Kr films (1,2,3, and 25 monolayers) physisorbed on Pt(111) along the (Γ¯ K¯)Kr azimuth. Phonon hybridization between the localized adlayer modes and the substrate Rayleigh wave is observed in the intersection region. Radiative damping causes a substantial phonon-linewidth broadening over the whole range where the adlayer modes overlap the substrate bulk bands.