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Magnetic Susceptibility of Multiorbital Systems

Katsunori Kubo·Takashi Hotta
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Abstract

Effects of orbital degeneracy on magnetic susceptibility in paramagnetic phases are investigated within a mean-field theory. Under certain crystalline electric fields, the magnetic moment consists of two independent moments, e.g., spin and orbital moments. In such a case, the magnetic susceptibility is given by the sum of two different Curie-Weiss relations, leading to deviation from the Curie-Weiss law. Such behavior may be observed in d- and f-electron systems with t_{2g} and Gamma_8 ground states, respectively. As a potential application of our theory, we attempt to explain the difference in the temperature dependence of magnetic susceptibilities of UO_2 and NpO_2.

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Katsunori Kubo, Takashi Hotta. 2005-12-26. Magnetic Susceptibility of Multiorbital Systems. https://doi.org/10.1143/jpsj.75.013702

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