Charge ordering and magnetism in the intermetallic oxides R<sub>5</sub>Pb<sub>3</sub>O (R = La-Sm)

ORAL

Abstract


The R5Pb3O family crystallizes in an interstitial derivative of the tetragonal Cr5B3 structure, in contrast to many hexagonal R5Pb3Z (Z = B, C, P) compounds. This structure features R-Pb chains along the c-axis. Despite being known for many years [1, 2], this family has remained largely unexplored until recently [3], with no physical properties reported for R = Pr-Sm compounds. In this talk, we present transport, magnetization, and diffraction measurements for R5Pb3O single crystals. Our experimental data, in agreement with theoretical calculations, support that the R5Pb3O (R = La and Ce) series hosts an electron-phonon coupling driven charge density wave (CDW) at low temperatures. The CDW ordering temperature is suppressed by more than 100 K by the La to Ce substitution, and X-ray diffraction indicates that the CDW is fully suppressed for R = Pr-Sm. Magnetic measurements reveal that the R = Pr-Sm members have ferrimagnetic structures with anomalously large coercive fields. Finally, high-pressure X-ray diffraction indicates structural transitions for the R = Pr-Sm, suggesting that the compression of R-Pb chains may stabilize new phases.


[1] Guloy et al. Z. Anorg. Allg. Chem. 616.10 (1992).


[2] Macaluso et al. Chem Mater. 16, 1560-1563 (2004).


[3] Penacchio et al. Phys. Rev. B, accepted on 18 September 2025. doi: 10.1103/c1qw-ddfn



*Work at Ames National Laboratory was supported by the U.S. DOE, Office of Basic Energy Science, DMSE. Ames National Laboratory is operated for the U.S. Department of Energy by Iowa State University under Contract No. DE-AC02- 07CH11358. This study was financed, in part, by FAPESP, Brazil. Proc. N. 2024/08497-6 and 2021/01004-6.

–

Publication: Charge density wave in the intermetallic oxides R5Pb3O (R = La and Ce)
Rafaela F. S. Penacchio, Siham Mohamed, Haley A. Harms, Sérgio L. Morelhão, Lin-Lin Wang, Sergey L. Bud'ko, Paul C. Canfield, and Tyler J. Slade

Phys. Rev. B - Accepted 18 September, 2025

DOI: https://doi.org/10.1103/c1qw-ddfn

Presenters

  • Rafaela Penacchio

    • AMES National Laboratory
    • University of Sao Paulo

Authors

  • Rafaela Penacchio

    • AMES National Laboratory
    • University of Sao Paulo

  • Siham Mohamed

    • Iowa State University

  • Haley Harms

    • University of Northern Iowa

  • Shuyuan huyan

    • Ames National Laboratory

  • Sergio L Morelhão

    • University of São Paulo
    • University of Sao Paulo

  • Lin-Lin Wang

    • Ames National Laboratory

  • Sergey L Bud'ko

    • Iowa State University

  • Paul C Canfield

    • Iowa State University
    • Ames National Laboratory and Department of Physics, Iowa State University, Ames, IA 50010.

  • Tyler J Slade

    • Ames National Laboratory