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Superexchange in the quarter- filled two- leg ladder system NaV2O5

V. Yushankhai·P. Thalmeier
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Abstract

A theory of superexchange in the mixed valent layer compound NaV2O5 is presented which provides a consistent description of exchange both in the disordered and charge ordered state. Starting from results of band structure calculations for NaV2O5 first an underlying electronic model for a ladder unit in the Trellis lattice is formulated. By using the molecular orbital representation for intra-rung electronic states a second-order perturbation procedure is developed and an effective spin-chain model for a ladder is derived. Variation of the resulting superexchange integral J is examined numerically as the ladder system evolves from a charge disordered to the extreme ('zig-zag') charge ordered state. It is found that the effective intra- ladder superexchange is always antiferromagnetic.

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V. Yushankhai, P. Thalmeier. 2000-08-22. Superexchange in the quarter- filled two- leg ladder system NaV2O5. https://doi.org/10.1103/physrevb.63.064402

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