Anomalous metallic and half-metallic properties of the Gd₄Sb₃ intermetallic compound

The electronic structure of the Sb-based intermetallic compound Gd₄Sb₃ has been studied, and it was recently revealed to have half-metallic properties [1]. Experimentally, anomalous Nernst and Hall effects were also found in Gd₄Sb_3, which confirmed the half-metallic behavior and anomalous electronic structure of this intermetallic compound [2]. Our calculations were performed according to an ab initio GGA+U method, which accounted for the strong electron correlations in the 4f shell of Gd. The ferromagnetic ordering in Gd₄Sb₃ is characterized by the large magnetic moment equal to 31 μ_B / f. u., which is mostly formed by the magnetic moments of the Gd ions. The band structure of Gd₄Sb₃ has interesting features which were revealed by our spin-polarized calculations. We found that one spin projection had completely metallic properties with multiple bands crossing the Fermi energy, whereas the other one was found to have an energy gap of 0.67 eV. Such features are absent in the binary semimetallic GdSb or metallic GdSb₂ compound with the close composition, which makes Gd₄Sb₃ a new, interesting half-metal ferromagnet with full spin polarization [1]. This research was supported by the Russian Science Foundation pr. No. 22-42-02021.

[1] Baidak, S. T.; Lukoyanov, A. V. Semimetallic, half-metallic, semiconducting, and metallic states in Gd-Sb compounds. Int. J. Mol. Sci. 2023, 24(10), 8778.

[2] Han, Y.; Qiu, C.; Ren, W.; et al. Anomalous Hall and Nernst effects in the half-metallic ferromagnet Gd₄Sb₃. Phys. Rev. B 2024, 110, 144405.