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Electronic structure and magnetism in X_xW_{1-x}O_3 (X=Nb,V,Re) from supercell calculations

T. Jarlborg
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Abstract

Some doped semiconductors have recently been shown to display superconductivity or weak ferromagnetism. Here we investigate the electronic structure and conditions for magnetism in a supercells of cubic XW_{26}O_{81}, where X=Nb,V and Re. The undoped material is an insulator, and although the slightly doped material is a metal, it is far from the Stoner criterion of magnetism. The conditions of a localized density-of-states which varies rapidly with the energy, resemble those of doped hexaborides. The virtual crystal approximation is used to vary the doping level. A small moment appears if the Fermi energy coincides with a large derivative of the DOS.

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T. Jarlborg. 2003-05-13. Electronic structure and magnetism in X_xW_{1-x}O_3 (X=Nb,V,Re) from supercell calculations. https://doi.org/10.1016/s0304-8853(03)00379-2

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