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arXiv · 0811.4643

Local spin and charge properties of beta-Ag0.33V2O5 studied by 51V NMR

A. Hisada·N. Fujiwara·T. Yamauchi·Y. Ueda
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Abstract

Local spin and charge properties were studied on beta-Ag0.33V2O5, a pressure-induced superconductor, at ambient pressure using 51V-NMR and zero-field-resonance (ZFR) techniques. Three inequivalent Vi sites (i=1, 2, and 3) were identified from 51V-NMR spectra and the principal axes of the electric-field-gradient (EFG) tensor were determined in a metallic phase and the following charge-ordering phase. We found from the EFG analysis that the V1 sites are in a similar local environment to the V3 sites. This was also observed in ZFR spectra as pairs of signals closely located with each other. These results are well explained by a charge-sharing model where a 3d1 electron is shared within a rung in both V1-V3 and V2-V2 two-leg ladders.

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A. Hisada, N. Fujiwara, T. Yamauchi, Y. Ueda. 2008-11-28. Local spin and charge properties of beta-Ag0.33V2O5 studied by 51V NMR. https://doi.org/10.1143/jpsj.78.094705

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