The electronic structure of Heusler-type Fe 2 VAl has been studied by high-resolution photoelectron spectroscopy with the excitation photon energy h# ranging from 21.2 eV (the He I laboratory light source) to 904 eV (the soft X-ray synchrotron light source) for clean surfaces prepared by scraping or fracturing polycrystalline and single crystalline specimens. Photoelectron spectra recorded for the fractured surfaces show a 10 eV-wide valence band with ®ne structures and a clear decrease in the intensity towards the Fermi level E F , while a high intensity at E F and no ®ne structures are observed for the scraped surface. Comparison with the theoretical density of states (DOS) indicates that the vacuum ultraviolet photoelectron spectra emphasize the transition-metal 3d bands but the soft X-ray photoelectron spectra agree remarkably well with the DOS including the ®ne structures and the pseudogap at E F . The present results suggest that the electronic structure of Fe 2 VAl is highly sensitive to possible strain and defects induced by scraping. Bulk electronic structures of Fe 2 VAl are discussed in relation to the reported fascinating transport properties.

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We have measured magnetic circular dichroism (MCD) spectra at the transition-metal L2,3 edges in D03-type (Fe(1-x)Mn(x))3Al in order to investigate their local magnetic moments. The analysis of the spectra shows that Fe has moments much larger than Mn, whose moment is ferromagnetically coupled with the Fe one. This does not lend support to the antiferromagnetic mechanism proposed for the reduction in magnetization as well as a large Mn moment predicted for x = 1/3. The evolution of satellites found in the Mn spectrum with x increased suggests that the change in the electronic state may result in the magnetization reduction.

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