Electronic Structure of FePc and Interface Properties on Ag(111) and Au(100)

The electronic structure of iron phthalocyanine (FePc) and interface properties on Ag(111) and Au(100) are investigated by photoexcited electron spectroscopies: photoemission (XPS and UPS) and X-ray absorption spectroscopy (XAS or NEXAFS). Valence band structures with Fe character were identified using resonant photoemission. The strength and nature of the interaction at the interface depend clearly on the substrate. A strong interaction of the central metal atom of the phthalocyanine occurs on Ag(111), whereas no significant changes of the electronic situation were found for FePc on Au(100). Resonant photoemission data show that for FePc on Ag(111) the formed interface states close to the Fermi level are determined by the interaction between Fe 3d states and substrate related states. On the other hand, also the nitrogen atom of FePc is involved in the interaction.