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Rung-singlet charge-ordering in alpha'-NaV2O5

R. T. Clay·S. Mazumdar
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Abstract

We show that the proposed zig--zag charge--ordering model for alpha'--NaV2O5 is incompatible with a single transition that induces both charge--ordering and spin gap. We introduce a two--band model for alpha'--NaV2O5 within which the simultaneous charge--spin order transition is driven principally by electron-phonon interactions. The spin gap is due to the formation of local dimers, thus explaining the weak magnetic effect on this transition.

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R. T. Clay, S. Mazumdar. 2003-05-20. Rung-singlet charge-ordering in alpha'-NaV2O5. https://arxiv.org/abs/cond-mat/0305479

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