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arXiv · 2005.10162

Electronic and magnetic properties of the Jahn-Teller active fluoride $\mathrm{NaCrF_{3}}$ from first-principles calculations

Jianghan Bao·Di Wang·Hai-Zhou Lu·Xiangang Wan
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Abstract

In perovskite-type compounds, the interplay of cooperative Jahn-Teller effect, electronic correlations and orbital degree of freedom leads to intriguing properties. $\mathrm{NaCrF_{3}}$ is a newly synthesized Jahn-Teller active fluoroperovskite where the $\mathrm{CrF_{6}^{4-}}$ octahedrons are considerably distorted. Based on the first-principles calculation, we analyze its electronic structure and magnetic properties. Our numerical results show that the $\mathrm{Cr^{2+}}$ ions adopt the high-spin $t_{2g\uparrow}^{3}e_{g\uparrow}^{1}$ configuration with $G$-type orbital ordering. We also estimate the magnetic exchange couplings and find that the in-plane and interplanar nearest-neighbor interactions are ferromagnetic and antiferromagnetic, respectively. The ground state of this material is $A$-type antiferromagnetic, in agreement with the experiments. Reasonable Curie-Weiss and $\mathrm{N\acute{e}el}$ temperatures compared to the experiments are given by mean-field approximation theory. Our results give a complete explanation of its electronic structure, magnetic and orbital order, and help to further comprehend the behaviors of Jahn-Teller active perovskite-type fluoride.

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Jianghan Bao, Di Wang, Hai-Zhou Lu, Xiangang Wan. 2020-05-20. Electronic and magnetic properties of the Jahn-Teller active fluoride $\mathrm{NaCrF_{3}}$ from first-principles calculations. https://doi.org/10.1103/physrevb.102.245142

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