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For the first time, the I-V-T dataset of a Schottky diode has been accurately modelled, parameterised, and fully fit, incorporating the effects of interface inhomogeneity, patch pinch-off and resistance, and ideality factors that are both heavily temperature and voltage dependent. A Ni/SiC Schottky diode is characterised at 2 K intervals from 20 to 320 K, which, at room temperature, displays low ideality factors (n < 1.01) that suggest that these diodes may be homogeneous. However, at cryogenic temperatures, excessively high (n > 8), voltage dependent ideality factors and evidence of the so-called "thermionic field emission effect" within a T0-plot, suggest significant inhomogeneity. Two models are used, each derived from Tung's original interactive parallel conduction treatment of barrier height inhomogeneity that can reproduce these commonly seen effects in single temperature I-V traces. The first model incorporates patch pinch-off effects and produces accurate and reliable fits above around 150 K, and at current densities lower than 10 À5 A cm À2. Outside this region, we show that resistive effects within a given patch are responsible for the excessive ideality factors, and a second simplified model incorporating these resistive effects as well as pinch-off accurately reproduces the entire temperature range. Analysis of these fitting parameters reduces confidence in those fits above 230 K, and questions are raised about the physical interpretation of the fitting parameters. Despite this, both methods used are shown to be useful tools for accurately reproducing I-V-T data over a large temperature range. V

Non-dipolar effects in the angular distribution of core level photoemission are shown to have a substantial influence on the interpretation of x-ray standing wavefield determinations of surface adsorption structures when the x-ray absorption is monitored by photoemission, even at photon energies below 3 keV. Results for I adsorption on Cu(111) are shown to be compatible with theoretical calculations for atomic Xe.

The interaction of methanethiol, CH3 SH, with Cu(100) has been studied by S 1s photoemission, S K-edge near-edge x-ray absorption fine structure and normal-incidence standing x-ray wavefield absorption at both (200) and (111) reflections. The results indicate that a single methanethiolate species, CH3 S-, is formed and this is bonded to the unreconstructed surface via the S atoms which adopt the fourfold symmetric hollow site. This conclusion confirms the results of a recent near-edge and surface extended x-ray absorption fine structure study, but contrasts with the established adsorbate-induced reconstruction produced by this species on Cu(111).

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