MAGNETIC EXCHANGE EFFECTS OF ADSORBATES ON THIN FE(110) FILMS

An angle and spin resolved photoemission study with very different spe cies on iron is presented. It was carried out with iodine, benzene, an d xenon on thin magnetized Fe(110) films grown layer-by-layer on W(110 ) by molecular beam epitaxy. For atomically adsorbed iodine a strong h ybridization occurs, leading to exchange split I 5p(x) and 5p(z) bands reflecting an induced magnetic moment of the iodine overlayer. The mo lecular adsorbate benzene shows no exchange splittings neither for the sigma nor for the pi orbitals being involved into the bonding to the substrate thus indicating a weaker hybridization between adsorbate and substrate bands. For physisorbed xenon, however, spin splittings occu r for both 5p levels due to a nonvanishing net magnetic moment of the ionic hole states leading to a magnetic coupling between substrate and adsorbate ion.