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Near degeneracy and pseudo Jahn-Teller effects in mixed-valence ladders: the phase transition in NaV$_2$O$_5$

L. Hozoi·S. Nishimoto·A. Yamasaki
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Abstract

We analyze the electronic structure of a mixed-valence ladder system. We find that structural anisotropy and complex electron correlations lead to on-rung charge localization and insulating character. Charge fluctuations within the rung of the ladder interact strongly to the lattice degrees of freedom, which gives rise to large pseudo Jahn--Teller effects. The phase transition in NaV$_2$O$_5$ should be driven by this kind of mechanism.

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L. Hozoi, S. Nishimoto, A. Yamasaki. 2005-02-10. Near degeneracy and pseudo Jahn-Teller effects in mixed-valence ladders: the phase transition in NaV$_2$O$_5$. https://doi.org/10.1103/physrevb.72.195117

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