Investigation of alkali metals and noble gases adsorbed on transition metals using circular dichroism in angular resolved photoemission

We investigated the adsorption of alkali metals an noble gases on transition metal surfaces. These serve as atom-like adsorbates to be comparable to calculations of the Circular Dichroism in the Angular Distribution of photoelectrons (CDAD) including backscattering at the substrate surface and photoelectron diffraction within the adsorbate layer. Our calculations show the influence of scattering and diffraction, that even can generate a dichroism where none should be. For the case of the 4p(1,2)-subshell of Rb our calculations agree well with our measurements. For the 4p(3/2)-subshell we found a different behaviour due to a polarisation of the state in the adsorbed layer. We also present first results for CDAD from noble gases. The 5p - states from Xe show less atomic-like behaviour, because they are much more weakly bound and form bands.