We investigate the electronic band structure of two of the rare-earth nitrides, DyN and SmN. Resistivity measurements imply that both materials have a semiconducting ground state, and both show resistivity anomalies coinciding with the magnetic transition, despite the different magnetic states in DyN and SmN. X-ray absorption and emission measurements are in excellent agreement with densities of states obtained from LSDA+U calculations, although for SmN the calculations predict a zero band gap.

The influence of shallow core-level hybridization on the electronic structure of the post-transition metal oxides ZnO, CdO, In 2 O 3 , and SnO 2 has been investigated using high-resolution soft x-ray emission and absorption spectroscopies. Synchrotron radiation excited O K ␣ emission spectra provide a direct measure of the O 2p partial density of states and shallow core-level hybridization for this series of transparent conducting materials and reveal significant mixing of O 2p and shallow-core metal d states for ZnO, CdO, and In 2 O 3 . The experimental data are compared with local density approximation and tight-binding band structure calculations and with previous experimental determinations of direct and indirect band gaps. Rocksalt CdO, bixbyite In 2 O 3 , and rutile SnO 2 all adopt structures with metal cations in sites with locally centrosymmetric coordination. This prevents hybridization of O 2p states with metal 4d states at the zone center, but mixing away from ⌫ leads to indirect band gaps for CdO and In 2 O 3 . A revised value for the lowest indirect band gap in CdO is proposed and the overall trends in the band gap are discussed in terms of the separation between O 2p and metal 4d states. The experimental investigation has been extended to study the effects of Sn doping in In 2 O 3 .

The electronic structure of thin films of the organic semiconductor vanadyl phthalocyanine has been studied using synchrotron radiation-excited resonant soft X-ray emission spectroscopy, resonant inelastic soft X-ray scattering, X-ray absorption spectroscopy, and X-ray photoemission spectroscopy. The C, N, V, and O partial densities of states for both the valence and conduction bands have been determined, as well as the core level electronic structure. Good agreement was found between the experimental measurements of the valence and conduction bands, and the results of a density functional calculation.

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