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Coulomb Correlations and Orbital Polarization in the Metal Insulator Transition of VO_2

A. Liebsch·H. Ishida·G. Bihlmayer
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Abstract

The quasi-particle spectra in the metallic rutile and insulating monoclinic phases of VO$_2$ are shown to be dominated by local Coulomb interactions. In the rutile phase the small orbital polarization among V 3d t_2g states leads to weak static but strong dynamical correlations. In the monoclinic phase the large 3d orbital polarization caused by the V--V Peierls distortion gives rise to strong static correlations which are shown to be the primary cause of the insulating behavior.

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A. Liebsch, H. Ishida, G. Bihlmayer. 2004-10-06. Coulomb Correlations and Orbital Polarization in the Metal Insulator Transition of VO_2. https://arxiv.org/abs/cond-mat/0310216

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