Electronic structure of cobalt phthalocyanine studied by resonant photoemission: Localization of Co-related valence band states

We study the electronic structure of cobalt phthalocyanine (CoPc) thin films on Au(1 0 0) using resonant photoemission spectroscopy and X-ray absorption spectroscopy (XAS). From XAS we conclude that the molecules are highly ordered and oriented parallel to the substrate surface. Cobalt related valence band states are identified using resonant photoemission. A strong enhancement of particular features is observed at the resonance energies, depending on the angle of incidence. This behavior can be understood by participator decay processes, the (de-)localization of Co-related valence band states is discussed.