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The electronic structure, mechanical and magnetic properties of Ni3Al, Ni3Ga and Ni3In have been studied by spin-density functional theory with generalized gradient approximation and also by X-ray absorption near-edge spectra (XANES) at the Ni, Ga K edges. The calculated lattice constants and bulk modulii are in good agreement with experiments. All three compounds have a similar calculated density of states (DOS) spectrum and are predicted to be a weak ferromagnet. The measured Ni(Ga) K-edge XANES are well explained by the theoretical XANES and unoccupied Ni(Ga)-p DOS, suggesting that XANES is a useful probe of the electronic structure of the intermetallics. [Copyright &y& Elsevier]

The electronic structures of two groups of intermetallic compounds and alloys containing Fe, V, or Ni are studied by X-ray absorption near-edge spectra (XANES) at the Fe, V, and Ni L2,3 edges and the Fe K edge. The XANES spectra are compared with those calculated with two theoretical methods. The differences in the XANES spectra of compounds containing Ni calculated by these two methods are discussed. Except for NiGa, a reasonable good agreement between theory and experiment was found for all materials. The density of states at the Fermi energy at different atomic sites are also calculated for the compounds and alloys containing Fe. [Copyright &y& Elsevier]

We present studies of orbital magnetic moments of CrO2 and Fe3O4 by measuring magnetic circular dichroism (MCD) in soft X-ray absorption. The results show that Fe3O4 exhibits large orbital moments, as a consequence of the strong Coulomb interactions of Fe 3d electrons. In contrast, orbital moments of Cr in CrO2 are nearly quenched, revealing that Cr 3d electrons are strongly hybridized with O 2p electrons and more delocalized as compared with those of Fe in Fe3O4. Comparing the MCD data with the band structure calculations based on local spin density approximation with on-site Coulomb energy U taken into account, we conclude that to include the on-site Coulomb interactions of 3d electrons is essential for adequately describing the electronic structure of CrO2 and Fe3O4. [Copyright &y& Elsevier]