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arXiv · 1410.5399

Metal-Insulator Transition and Lattice Instability of Paramagnetic V2O3

I. Leonov·V. I. Anisimov·D. Vollhardt
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Abstract

We determine the electronic structure and phase stability of paramagnetic V$_2$O$_3$ at the Mott-Hubbard metal-insulator phase transition, by employing a combination of an ab initio method for calculating band structures with dynamical mean-field theory. The structural transformation associated with the metal-insulator transition is found to occur upon a slight expansion of the lattice volume by $\sim 1.5$ %, in agreement with experiment. Our results show that the structural change precedes the metal-insulator transition, implying a complex interplay between electronic and lattice degrees of freedom at the transition. Electronic correlations and full charge self-consistency are found to be crucial for a correct description of the properties of V$_2$O$_3$.

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I. Leonov, V. I. Anisimov, D. Vollhardt. 2015-05-18. Metal-Insulator Transition and Lattice Instability of Paramagnetic V2O3. https://doi.org/10.1103/physrevb.91.195115

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