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The deposition and subsequent decomposition of a cyclopentadienyl-allyl-palladium precursor on a Pd(111) single crystal was investigated by a combination of X-ray photoelectron spectroscopy (XPS) and near edge X-ray absorption fine structure (NEXAFS) spectroscopy. Because the precursor decomposes readily on metal surfaces, a deposition system with its inner surfaces completely covered by chemically inert materials such as glass or Teflon was used to keep the precursor molecules intact prior to the deposition process. Upon adsorption on the palladium substrate surface, the precursor molecules are chemically modified even at temperatures as low as 170 K. At higher temperatures, the precursor decomposes, the oxidation state of the palladium changes from +2 to 0, and the ligands remain adsorbed at the palladium surface. Attempts to remove the hydrocarbon ligands by etching with molecular hydrogen were not successful.

The adsorption of ethylbenzene and styrene on well ordered epitaxial iron oxide model catalyst films with different stoichiometries was investigated using near edge X-ray absorption fine structure spectroscopy (NEXAFS). On the iron-terminated Fe3O4(111) and a?Fe2O3(0001) surfaces a chemisorption of ethylbenzene and styrene is observed which initially occurs on the iron sites via the p-electron system of the phenyl ring. This forces the molecules into an almost flat lying configuration (h6 like ring adsorption geometry). In the case of ethylbenzene this adsorption complex is supposed to lead to an activation of the C-H bonds thus facilitating the dehydrogenation to styrene. The tilt angle of the aromatic ring systems increase to about 40° when approaching monolayer saturation. In contrast, the interaction with the oxygen-terminated FeO(111) surface is weak and of the physisorption type. The adsorbate-adsorbate interaction dominates and causes a tilted adsorption of the molecules from the beginning.

The photo-generation of optical anisotropy is investigated in spin-coated films of two liquid crystalline polymers containing differently substituted azobenzene side groups upon irradiation with linearly polarized light. UV spectroscopy with polarised light, waveguide spectroscopy and NEXAFS (Near Edge X-ray Absorption Fine Structure) spectroscopy have been used to characterize the photoinduced order within the film and at the surface. While azimuthal anisotropy is observed in the volume of both polymers, surface anisotropy is only found in case of the homopolymer. The azobenzene moieties of the copolymer do not show any out-of-plane orientation at the surface.

The adsorption of styrene on (111)-oriented thin layers of FeO and Fe3O4 epitaxially grown on Pt(111) single-crystal surfaces has been investigated using near-edge X-ray absorption fine structure (NEXAFS) spectroscopy and X-ray photoelectron spectroscopy (XPS). High-resolution gas-phase measurements were recorded, and precise ab initio electronic structure calculations were performed in order to aid the assignment of the NEXAFS resonances. Whereas on Fe3O4 (magnetite), styrene forms a chemisorbed monolayer that is stable up to room temperature, on FeO (wustite), a significantly more weakly bound (physisorbed) species is observed that is stable only for temperatures below 200 K. A planar adsorption geometry is observed in the case of styrene on Fe3O4 in the low-coverage regime (ϑ < 0.5 ML); for higher coverages on the same surface and on FeO, the average tilt angle between the phenyl plane and the surface plane amounts to about 45°.