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arXiv · 0805.3892

Frustration-induced valence bond crystal and its melting in Mo3Sb7

T. Koyama·H. Yamashita·Y. Takahashi·T. Kohara·I. Watanabe·Y. Tabata·H. Nakamura
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Abstract

121/123Sb nuclear quadrupole resonance and muon spin relaxation experiments of Mo3Sb7 revealed symmetry breakdown to a nonmagnetic state below the transition recently found at TS=50 K. The transition is characterized by a distinct lattice dynamics suggested from narrowing of nuclear fields. We point out that the Mo sublatice is a unique three-dimensional frustrated lattice where nearest-neighbor and next-nearest-neighbor antiferromagnetic interactions compete, and propose that tetragonal distortion to release the frustration stabilizes long-range order of spin-singlet dimers, i.e., valence bond crystal, which is thermally excited to the dynamic state with cubic symmetry.

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T. Koyama, H. Yamashita, Y. Takahashi, T. Kohara, I. Watanabe, Y. Tabata, H. Nakamura. 2008-05-26. Frustration-induced valence bond crystal and its melting in Mo3Sb7. https://doi.org/10.1103/physrevlett.101.126404

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