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arXiv · 1705.10734

Zeeman interaction and Jahn-Teller effect in $\Gamma_8$ multiplet

Naoya Iwahara·Veacheslav Vieru·Liviu Ungur·Liviu F. Chibotaru
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Abstract

We present a thorough analysis of the interplay of magnetic moment and the Jahn-Teller effect in the $\Gamma_8$ cubic multiplet. We find that in the presence of dynamical Jahn-Teller effect, the Zeeman interaction remains isotropic, whereas the $g$ and $G$ factors can change their signs. The static Jahn-Teller distortion also can change the sign of these $g$ factors as well as the nature of the magnetic anisotropy. Combining the theory with state-of-the-art {\it ab initio} calculations, we analyzed the magnetic properties of Np$^{4+}$ and Ir$^{4+}$ impurity ions in cubic environment. The calculated $g$ factors of Np$^{4+}$ impurity agree well with experimental data. The {\it ab initio} calculation predicts strong Jahn-Teller effect in Ir$^{4+}$ ion in cubic environment and the strong vibronic reduction of $g$ and $G$ factors.

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Naoya Iwahara, Veacheslav Vieru, Liviu Ungur, Liviu F. Chibotaru. 2017-05-30. Zeeman interaction and Jahn-Teller effect in $\Gamma_8$ multiplet. https://doi.org/10.1103/physrevb.96.064416

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