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arXiv · 1503.02462

Exchange interaction between $J$-multiplets

Naoya Iwahara·Liviu F. Chibotaru
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Abstract

Analytical expressions for the exchange interaction between $J$-multiplets of interacting metallic centers are derived on the basis of a complete electronic model. A common belief that this interaction can be approximated by an isotropic form $\propto {\mathbf{J}}_1\cdot{\mathbf{J}}_2$ (or $\propto {\mathbf{J}}_1\cdot{\mathbf{S}}_2$ in the case of interaction with an isotropic spin) is found to be ungrounded. It is also shown that the often used "1/U approximation" for the description of the kinetic contribution of the exchange interaction is not valid in the case of $J$-multiplets. The developed theory can be used for microscopic description of exchange interaction in materials containing lanthanides, actinides and some transition metal ions.

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Naoya Iwahara, Liviu F. Chibotaru. 2015-05-28. Exchange interaction between $J$-multiplets. https://doi.org/10.1103/physrevb.91.174438

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