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arXiv · 0805.1670

Homopolar bond formation in ZnV$_2$O$_4$ close to a metal-insulator transition

V. Pardo·S. Blanco-Canosa·F. Rivadulla·D. I. Khomskii·D. Baldomir·Hua Wu·J. Rivas
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Abstract

Electronic structure calculations for spinel vanadate ZnV$_2$O$_4$ show that partial electronic delocalization in this system leads to structural instabilities. These are a consequence of the proximity to the itinerant-electron boundary, not being related to orbital ordering. We discuss how this mechanism naturally couples charge and lattice degrees of freedom in magnetic insulators close to such a crossover. For the case of ZnV$_2$O$_4$, this leads to the formation of V-V dimers along the [011] and [101] directions that readily accounts for the intriguing magnetic structure of ZnV$_2$O$_4$.

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V. Pardo, S. Blanco-Canosa, F. Rivadulla, D. I. Khomskii, D. Baldomir, Hua Wu, J. Rivas. 2008-05-12. Homopolar bond formation in ZnV$_2$O$_4$ close to a metal-insulator transition. https://doi.org/10.1103/physrevlett.101.256403

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