[en] This thesis comprises a detailed study of the electronic properties of the polycyclic hydrocarbons tetracene, perylene and coronene. The at room temperature grown organic layers consisted of a up to several hundred nanometer thickness, and have been studied with the experimental techniques soft X-ray emission spectroscopy (SXES) and NEXAFS-spectroscopy by means of synchrotron radiation. In particular, resonant inelastic scattering (RIXS) was employed in order to obtain possible band structure or MO-symmetry information of the studied systems. The studied materials consist of large organic molecules, evaporated under high vacuum on silicon wafers. The goal was to figure out, whether inside these organic layers the hydrocarbon molecules polymerize and form a band structure or if the hydrocarbon molecules do not interact with each other and retain their original molecular like symmetry and behavior. The discrete peaks in the hydrocarbon NEXAFS-spectra could be assigned by comparison with the literature to chemical shifted C1s→ π^* transitions, caused by different chemical surrounded C-atoms. Hence, due to excitation on a certain π^*-resonance only C1s-electrons of equal C-atoms can be excited, which leads to a site selective excitation. The fluorescent decay of the created hole, which is as well localized on these former excited C-atoms was recorded energy dispersed in the SXE-spectrometer. This method is usually referred to as SXE. Therefore, the local MO-density was recorded. Hartree-Fock based ground state MO-calculations have been performed for each molecule, in order to simulate the SXE-spectra. Good agreement between experiment and simulation was shown, under the strict retainment of symmetry selection rules along the transitions. This result states, that the different hydrocarbon molecules conserve their symmetry and structure in an up to several hundred nanometer thick organic layer. Only in the region of the valence band maximum (π-states) weak indications for a band dispersion could be observed. (orig.)

[en] This report for the Swiss Federal Office of Energy presents a proposal on how to revise and extend the Swiss energy consumption statistics regarding the industrial sector. Companies and officials admitted that the current procedure is no longer satisfactory, because of systematic bias related to the applied procedure. As the introduction of a tax on CO₂ emissions is most probable in Switzerland, the energy consumption figures used to calculate the tax shall be incontestable. The suggested procedure described in the report fulfils this requirement. Instructions for the data collection are given together with the forms to be used in the survey, distinguishing the energy sources. Detailed indications on how many companies shall be randomly selected in each of the 18 industrial sectors (both manufacturing and services) and each of the categories 'small', 'middle-size' and 'large companies' have ben established. In this way, data extrapolation for the whole industrial sector will be reliable. Both the official offices and the industry representatives agreed to the suggested procedure. The sectorial structure has been defined in accordance with international practice

[en] In coherent soft x-ray scattering from magnetically ordered surfaces there are contributions to the scattering from the magnetic domains, from the surface roughness, and from the diffraction associated with the pinhole aperture used as a coherence filter. In the present work, we explore the interplay between these contributions by analyzing speckle patterns in diffusely scattered x rays from the surface of magnetic thin films. Magnetic contrast from the surface of anti ferro magnetically ordered LaFeO3 films is caused by magnetic linear dichroism in resonant x-ray scattering. The samples studied possess two types of domains with their magnetic orientations perpendicular to each other. By tuning the x-ray energy from one of the two Fe-L3 resonant absorption peaks to the other, the relative amplitudes of the x-ray scattering from the two domains is inverted which results in speckle pattern changes. A theoretical expression is derived for the intensity correlation between the speckle patterns with the magnetic contrast inverted and not inverted. The model is found to be in good agreement with the x-ray-scattering observations and independent measurements of the surface roughness. An analytical expression for the correlation function gives an explicit relation between the change in the speckle pattern and the roughness, and magnetic and aperture scattering. Changes in the speckle pattern are shown to arise from beating of magnetic scattering with the roughness scattering and diffraction from the aperture. The largest effect is found when the surface roughness scatter is comparable in intensity to the magnetic scatter

[en] Beryllium isotopes (⁹Be and ¹⁰Be) distribution in Holocene and late Pleistocene glacial ice and sediment facies from sub-ice stream and sub-ice shelf settings of the Ross sector of the West Antarctic Ice Sheet (WAIS) and from the open Ross Sea are presented, to assess the temporal and spatial variability of these tracers. Significant variation is detected (>one order of magnitude) among Holocene post-glacial deposits. Late Pleistocene diamictons from bathymetric lows in the Ross Sea show depleted concentrations that are less variable among sites and distinctly lower than bank deposits of similar age. In general, sub-ice shelf and ice stream sediments are the most depleted in ¹⁰Be. ¹⁰Be with its longer half-life and different pathways compared apparant to ¹⁴C is found to be a sensitive marker for evaluating the complex spatial and temporal relationships between texturally similar sediments formed by different depositional processes

[en] In coherent soft x-ray scattering from magnetically ordered surfaces there are contributions to the scattering from the magnetic domains, from the surface roughness, and from the diffraction associated with the pinhole aperture used as a coherence filter. In the present work, we explore the interplay between these contributions by analyzing speckle patterns in diffusely scattered x rays from the surface of magnetic thin films. Magnetic contrast from the surface of antiferromagnetically ordered LaFeO₃ films is caused by magnetic linear dichroism in resonant x-ray scattering. The samples studied possess two types of domains with their magnetic orientations perpendicular to each other. By tuning the x-ray energy from one of the two Fe-L₃ resonant absorption peaks to the other, the relative amplitudes of the x-ray scattering from the two domains is inverted which results in speckle pattern changes. A theoretical expression is derived for the intensity correlation between the speckle patterns with the magnetic contrast inverted and not inverted. The model is found to be in good agreement with the x-ray-scattering observations and independent measurements of the surface roughness. An analytical expression for the correlation function gives an explicit relation between the change in the speckle pattern and the roughness, and magnetic and aperture scattering. Changes in the speckle pattern are shown to arise from beating of magnetic scattering with the roughness scattering and diffraction from the aperture. The largest effect is found when the surface roughness scatter is comparable in intensity to the magnetic scatter