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arXiv · 1912.07770

Three Jahn-Teller states of matter in the spin-crossover system Mn(taa)

Jie-Xiang Yu·Dian-Teng Chen·Jie Gu·Jia Chen·Jun Jiang·Long Zhang·Yue Yu·Xiao-Guang Zhang·Vivien S. Zapf·Hai-Ping Cheng
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Abstract

Three high-spin phases recently discovered in the spin-crossover system Mn(taa) are identified through analysis by a combination of first-principles calculations and Monte Carlo simulation as a low-temperature Jahn-Teller ordered (solid) phase, an intermediate-temperature dynamically correlated (liquid) phase, and an uncorrelated (gas) phase. In particular, the Jahn-Teller liquid phase arises from competition between mixing with low-spin impurities, which drive the disorder, and inter-molecular strain interactions. The latter are a key factor in both the spin-crossover phase transition and the magnetoelectric coupling. Jahn-Teller liquids may exist in other spin-crossover materials and materials that have multiple equivalent Jahn-Teller axes.

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Jie-Xiang Yu, Dian-Teng Chen, Jie Gu, Jia Chen, Jun Jiang, Long Zhang, Yue Yu, Xiao-Guang Zhang, Vivien S. Zapf, Hai-Ping Cheng. 2020-05-02. Three Jahn-Teller states of matter in the spin-crossover system Mn(taa). https://doi.org/10.1103/physrevlett.124.227201

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