Abstract
The electronic structure and charge states of atoms of cubic and hexagonal tantalum carbides have been studied by X-ray photoelectron (XPS) and X-ray absorption (XAS) spectroscopy. The XPS spectra of both valence and core-level electrons as well as the TaL III XAS spectra of TaCx have been obtained over the range 0.36≤x≤0.98. In all the tantalum carbides studied charge transfer takes place from Ta to C atoms. The shifts of the Ta 4f core levels and the midpoints of the TaLIII absorption edges indicates that the effective positive charge of the Ta atoms decreases in the row TaC0.98»TaC0.36. In that sequence of compounds the main peak of the XPS valence band spectra shifts toward the Fermi level by about 0.85 eV.
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Institute for Problems of Materials Science, Ukraine National Academy of Sciences, Kiev. Translated from Poroshkovaya Metallurgiya, Nos. 5-6(407), pp. 82–91, May–June, 1999.
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Khyzhun, O.Y. Electronic structure and charge state of atoms of cubic and hexagonal tantalum carbides. Powder Metall Met Ceram 38, 284–291 (1999). https://doi.org/10.1007/BF02675777
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DOI: https://doi.org/10.1007/BF02675777