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We investigated the structural and electronic properties of vacuum sublimed perfluoro-pentacene ͑PFP͒ thin films on Ag͑111͒ substrates using x-ray standing waves ͑XSW͒, x-ray diffraction ͑XRD͒ and ultraviolet photoelectron spectroscopy ͑UPS͒. XSW results reveal a flat adsorption geometry of the monolayer PFP/Ag͑111͒ with a relatively large bonding distance of 3.16 Å for both, the carbon and fluorine atoms. Multilayers PFP/Ag͑111͒ adopt a herringbone structure with the molecular long axis parallel to the substrate and a vertical lattice spacing of 3.06 Å as evidenced by XRD. The strong intramolecular polar bond character of the fluorine-carbon bonds in PFP leads to an orientation dependent ionization energy ͑IE͒ that is experimentally observed by UPS for the monolayer-multilayer transition: The inclined molecular plane orientation in the multilayer herringbone arrangement leads to an increase of the PFP IE by Ͼ0.4 eV compared to the flat lying monolayer.

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The hole–phonon coupling of a rubrene monolayer on graphite is measured by means of angle resolved ultraviolet photoelectron spectroscopy. Thus, the charge reorganization energy λ and the small polaron binding energy is determined, which allows insight into the nature of charge transport in condensed rubrene.

Electron−phonon coupling of the highest occupied molecular orbital (HOMO) state is studied by high-resolution ultraviolet photoelectron spectroscopy (UPS) for pentacene (PEN) and perfluoropentacene (PFP) monolayers on graphite. The reorganization energy and related coupling constants associated with the interaction between holes and molecular vibrations are obtained experimentally using a single mode analysis (SMA) of the observed vibronicsatellite intensities of the monolayers. The results are compared with those estimated by multimode analyses of UPS spectra and those derived by means of theoretical approaches, indicating that the purely experimental method with SMA is useful for studying the reorganization energy and the hopping mobility of organic systems. Furthermore, we found that the reorganization energy of PFP is significantly greater than that of PEN, which is ascribed to the extended HOMO distribution of PFP by perfluorination of PEN. The comparison with the results derived from gas-phase UPS measurements is also discussed.