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Role of c-axis pairs in V2O3 from the band-structure point of view

I. S. Elfimov·T. Saha-Dasgupta·M. A. Korotin
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Abstract

The common interpretation of the LDA band structure of V$_{2}$O$_{3}$ is that the apparent splitting of the $a_{1g}$ band into a low intensity structure deep below the Fermi energy and a high intensity feature above it, is due to the bonding-antibonding coupling of the vertical V-V pair. Using tight-binding fitting to --as well as first-principles NMTO downfolding of-- the spin-up LDA+U $a_{1g}$ band, we show that there are other hopping integrals which are equally important for the band shape as the integral for hopping between the partners of the pair.

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I. S. Elfimov, T. Saha-Dasgupta, M. A. Korotin. 2003-07-07. Role of c-axis pairs in V2O3 from the band-structure point of view. https://doi.org/10.1103/physrevb.68.113105

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