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The magnetic ordering in the mixed valence compound beta-Na0.33V2O5

A. N. Vasil'ev·V. I. Marchenko·A. I. Smirnov·S. S. Sosin·H. Yamada·Y. Ueda
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Abstract

The low-temperature electron spin resonance (ESR) spectra and the static magnetization data obtained for the stoichiometric single crystals of $β$-Na$_{0.33}$V$_2$O$_5$ indicate that this quasi-one-dimensional mixed valence (V4+/V5+) compound demonstrates at $T_N=22$ K the phase transition into the canted antiferromagnetically ordered state. The spontaneous magnetization of $3.4\times 10^{-3}$ $μ_B$ per V$^{4+}$ ion was found to be oriented along the two-fold $b$ axis of the monoclinic structure, the vector of antiferromagnetism is aligned with the $a$ axis and the Dzyaloshinsky vector is parallel to the $c$-axis. The experimental data were successfully described in the frame of the macroscopic spin dynamics and the following values for the macroscopic parameters of the spin system were obtained: the Dzyaloshinsky field $H_D=6$ kOe, the energy gaps of two branches of the spin wave spectrum $Δ_1=48$ GHz and $Δ_2=24$ GHz.

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A. N. Vasil'ev, V. I. Marchenko, A. I. Smirnov, S. S. Sosin, H. Yamada, Y. Ueda. 2000-12-22. The magnetic ordering in the mixed valence compound beta-Na0.33V2O5. https://doi.org/10.1103/physrevb.64.174403

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