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arXiv · 0804.0990

First-Principles Study of Correlation Effects in VO2: Peierls vs. Mott-Hubbard

R. Sakuma·T. Miyake·F. Aryasetiawan
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Abstract

We present a study of VO2 in the rutile and monoclinic (M1) phases by means of all-electron full-potential LMTO GW calculation. Full frequency dependence and the off-diagonal matrix elements of the self-energy are taken into account. As a result of dynamical correlation, a satellite structure is found above the $t_{2g}$ quasiparticle peak but not below, in both the rutile and monoclinic phases. For the monoclinic structure, the insulating state is not obtained within the usual 1-shot GW calculation. We perform a simplified "self-consistent" GW scheme by adding a uniform shift to the conduction band levels and recalculating the quasiparticle wavefunctions accordingly. An insulating solution with a gap of approximately 0.6 eV is obtained, in agreement with experiments.

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R. Sakuma, T. Miyake, F. Aryasetiawan. 2008-04-07. First-Principles Study of Correlation Effects in VO2: Peierls vs. Mott-Hubbard. https://arxiv.org/abs/0804.0990

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