Exchange splitting of photoemission lines in GdF₃ and metallic Gd compounds

X-ray photoelectron spectroscopy was used to study the electronic structure of bulk GdF₃, Gd₂In and Gd₅Si₄. The structure of the Gd photoemission core level multiplets was analysed and compared to that one obtained for Gd metal. The line-width and the intensity ratio of the component lines within the multiplets were found to be dependent on the compound. The observed effects have been related to the variation of the valence band structure and various hybrydization effects between the 4f electrons and conduction or valence ones. The most modified multiplet structure in relation to Gd metal was found in the ionic compound GdF₃.