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Charge Order Driven spin-Peierls Transition in NaV2O5

Y. Fagot-Revurat·M. Mehring·R. K. Kremer
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Abstract

We conclude from 23Na and 51V NMR measurements in NaxV2O5(x=0.996) a charge ordering transition starting at T=37 K and preceding the lattice distortion and the formation of a spin gap Delta=106 K at Tc=34.7 K. Above Tc, only a single Na site is observed in agreement with the Pmmn space group of this first 1/4-filled ladder system. Below Tc=34.7 K, this line evolves into eight distinct 23Na quadrupolar split lines, which evidences a lattice distortion with, at least, a doubling of the unit cell in the (a,b) plane. A model for this unique transition implying both charge density wave and spin-Peierls order is discussed.

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Y. Fagot-Revurat, M. Mehring, R. K. Kremer. 1999-07-21. Charge Order Driven spin-Peierls Transition in NaV2O5. https://doi.org/10.1103/physrevlett.84.4176

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