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Abstract: We have investigated the electronic properties of a thin film of ZnPcCl8 molecules deposited on Ag(111) using ultra-violet photoelectron spectroscopy. Close to one monolayer the electronic structure differs sensibly from that of the thick film. The appearance of a density of states close to the Fermi level is interpreted as the sign of the molecule–substrate interaction via a charge transfer mechanism. An increase of the work function at the early stages of adsorption confirms that electrons are transferred from the metal to the molecular orbitals creating an interface dipole. As the coverage is increased the weak interaction between molecules of successive layers causes the electronic properties to evolve gradually towards those of the thick film. Finally, the impact of the interface electronic properties on the intermolecular interaction is discussed. [Copyright &y& Elsevier]

The C60 molecules are known to bind covalently to the Pt(1 1 1) surface. We performed a structural study of one C60 layer on Pt(1 1 1) by using X-ray photoelectron diffraction (XPD). Our results show that the molecules are bonded to the metal surface with their six-carbon rings facing the Pt(1 1 1) surface and with the C&z.sbnd;C bonds perpendicularly oriented with respect to the direction of the close-packed atom rows. Unlike to what previously found for Cu(1 1 1) and Al(1 1 1), the measured diffraction pattern shows a three-fold symmetry indicating that only one orientation is taken by the chemisorbed molecules. This can be explained by a stronger interaction of the C60 molecules with the second layer Pt atoms. [Copyright &y& Elsevier]

Abstract: We report on a combined photoemission and inverse photoemission spectroscopy analysis on RbxC60 compounds with different stoichiometries (). Apart from shifts and broadening of the spectral features associated to the different phase formed, we observe in the RbC60 phase the presence of the highest occupied molecular orbital (HOMO) shoulder and of its symmetric (with respect to the Fermi level) empty state. According to calculations, the metallicity of this phase and the presence of these electronic states may be taken as a fingerprint of the interplay between electron–electron and electron–phonon interactions in determining the electronic behavior of alkali metal fullerides. [Copyright &y& Elsevier]

A number of recent results indicate that C60 films can superconduct at considerably high temperatures. The response of a material to impurities can give an information about its superconducting properties when more conventional methods for spotting superconductivity are difficult to apply. While magnetic impurities act as strong Cooper pair breakers in conventional superconductors, nonmagnetic impurities have none or negligible effect. We investigated the influence of magnetic and nonmagnetic impurities on the electronic structure of one monolayer C60 on Ag(1 0 0). Preliminary results show that the gap persists in the presence of nonmagnetic Au but it is completely suppressed in the presence of magnetic Fe, as expected for a superconductor. This result gives a support for the possible superconducting scenario in one monolayer C60 on Ag(1 0 0) and certainly requires additional experiments to be performed to assure the superconducting character of the film. [Copyright &y& Elsevier]

The surface properties of SnO2(1 1 0)-4×1 and sputtered SnO2(1 1 0) were studied comparatively by resonant photoemission of the valence band states in a photon energy range of 60–130 eV. Resonating energetic levels could be observed on the 4×1 reconstructed surface and the resonance behavior could be switched off by sputter treatment. Additionally, the Sn 4d core-levels were recorded at two photon energies in order to allow a statement about the surface''s stoichiometry. A tentative explanation of the observed resonance and of the discrepancy between ordered and sputtered surface is given with regard to recent STM results on similar prepared surfaces. [Copyright &y& Elsevier]