Importance of interorbital charge transfers for the metal-to-insulator transition of BaVS$_3$

Frank Lechermann; Silke Biermann; Antoine Georges

doi:10.1103/physrevlett.94.166402

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Importance of interorbital charge transfers for the metal-to-insulator transition of BaVS$_3$

Frank Lechermann·Silke Biermann·Antoine Georges

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Abstract

The underlying mechanism of the metal-to-insulator transition (MIT) in BaVS$_3$ is investigated, using dynamical mean-field theory in combination with density functional theory. It is shown that correlation effects are responsible for a strong charge redistribution, which lowers the occupancy of the broader \a1g band in favor of the narrower $E_g$ bands. This resolves several discrepancies between band theory and the experimental findings, such as the observed value of the charge-density wave ordering vector associated with the MIT, and the presence of local moments in the metallic phase.

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Frank Lechermann, Silke Biermann, Antoine Georges. 2004-12-14. Importance of interorbital charge transfers for the metal-to-insulator transition of BaVS$_3$. https://doi.org/10.1103/physrevlett.94.166402

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