The low energy dynamics of adsorbates on metal surfaces investigated with helium atom scattering

High resolution helium atom scattering (HAS) has proved to be a useful probe of the low frequency (<20 meV, <160 cm−1) dynamics of adsorbates on metal surfaces including diffusion and vibrations. In the present paper the results of the HAS measurements obtained so far are reviewed and compared with some of the current theoretical models. In addition, the vibrational frequency trends for selected adsorbates on different metal surfaces are analyzed. Some details of the HAS data analysis are also considered and compared with results from other methods.