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Localization in ruthenates: magnetic and electronic properties of Ca(2-x)Sr(x)RuO(4)

V. I. Anisimov·I. A. Nekrasov·D. E. Kondakov·T. M. Rice·M. Sigrist
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Abstract

The electronic structures of the metallic and insulating phases of Ca(2-x)Sr(x)RuO(4) (0<= x <= 2) are calculated using LDA, LDA+U and Dynamical Mean-Field Approximation methods. For x=0 the ground state is an orbitally non-degenerate antiferromagnetic insulator. For 0.2 0.5 the observed Curie-Weiss paramagnetic metallic state possessing a local moment with the unexpected spin S=1/2 is explained by the localization of only two of the three Ru-4d-orbitals.

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V. I. Anisimov, I. A. Nekrasov, D. E. Kondakov, T. M. Rice, M. Sigrist. 2000-11-28. Localization in ruthenates: magnetic and electronic properties of Ca(2-x)Sr(x)RuO(4). https://arxiv.org/abs/cond-mat/0011460

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