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Charge Ordering and Spin gap in NaV_2O_5

Hitoshi Seo·Hidetoshi Fukuyama
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Abstract

A possible ground state of NaV_2O_5 is proposed based on the Hartree approximation for both on-site and intersite Coulomb interactions. The results indicate that the intersite Coulomb interaction induces a zigzag type of charge disproportionation (i.e. charge ordering) along the ladders of V-ions resulting in the localized spins between neighboring ladders to form a spin gap. This new state, which is different from the spin-Peierls state so far believed, seems to be consistent with the existing experimental results.

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Hitoshi Seo, Hidetoshi Fukuyama. 1998-05-15. Charge Ordering and Spin gap in NaV_2O_5. https://doi.org/10.1016/s0022-3697(99)00056-6

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