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Magnetic anisotropy and intermediate valence in CeCo5 ferromagnet

Alexander B. Shick* and Evgenia A. Tereshina-Chitrova

  • *Contact author: shick@fzu.cz
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Phys. Rev. Research 8, 023079 – Published 27 April, 2026

DOI: https://doi.org/10.1103/k5st-k138

Abstract

The intermediate valence of Ce in CeCo5 challenges standard density functional theory (DFT) and static DFT+U approaches, which fail to capture its magnetic properties. By combining DFT+U with exact diagonalization of the Anderson impurity model for the Ce 4f shell, we find a substantial reduction of Ce spin and orbital moments, consistent with DFT+DMFT (dynamical mean-field theory), arising from Ce4+−Ce3+ valence fluctuations. The total magnetic moment of 6.70 µB agrees with experiment, and the calculated 4f density of states reproduces photoemission and bremsstrahlung isochromat spectra. The uniaxial magnetic anisotropy energy reaches 4.8 meV/f.u. when Coulomb correlations on both Ce 4f and Co 3d shells are included, in very good agreement with experimental data. These results highlight the importance of dynamical correlations and provide guidance for exploring high-performance, low-rare-earth-content permanent magnets.

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Phys. Rev. Research 8, 023079– Published 27 April, 2026
  • Received 1 October 2025
  • Accepted 30 March 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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