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Spin and orbital frustration in MnSc_2S_4 and FeSc_2S_4

V. Fritsch·J. Hemberger·N. Buettgen·E. W. Scheidt·H. A. Krug von Nidda·A. Loidl·V. Tsurkan
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Abstract

Crystal structure, magnetic susceptibility, and specific heat were measured in the normal cubic spinel compounds MnSc_2S_4 and FeSc_2S_4. Down to the lowest temperatures, both compounds remain cubic and reveal strong magnetic frustration. Specifically the Fe compound is characterized by a Curie-Weiss temperature Θ_{CW}= -45 K and does not show any indications of order down to 50 mK. In addition, the Jahn-Teller ion Fe^{2+} is orbitally frustrated. Hence, FeSc_2S_4 belongs to the rare class of spin-orbital liquids. MnSc_2S_4 is a spin liquid for temperatures T > T_N \approx 2 K.

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V. Fritsch, J. Hemberger, N. Buettgen, E. W. Scheidt, H. A. Krug von Nidda, A. Loidl, V. Tsurkan. 2004-02-19. Spin and orbital frustration in MnSc_2S_4 and FeSc_2S_4. https://doi.org/10.1103/physrevlett.92.116401

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