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Self-organized vacancy order in Pr9Ge16

Jayashani S. T. Wickramasinghe1, Melissa G. Anderson2, Kelci Graville1, Gregory T. McCandless2, Zachary J. Morgan3, Brianna R. Billingsley4, Tai Kong4, Hyunsoo Kim1,5, Aleksandr V. Chernatynskiy1 et al.

Simon G. Mitchell6, Liang Wu6, Julia Y. Chan2, Feng Ye3, and Halyna Hodovanets1,5,*

  • *Contact author: halyna.hodovanets@mst.edu
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Phys. Rev. Materials 10, 084401 – Published 5 August, 2026

DOI: https://doi.org/10.1103/1jfr-6fkb

Abstract

In this work, we report the discovery of a new crystal structure on the Ge-rich side of the Pr-Ge binary phase diagram. Using a high-temperature flux technique, we grew single crystals of Pr9Ge16, which adopt a previously unreported orthorhombic Fdd2 structure type featuring ordered Ge vacancies. We present the anisotropic magnetic properties and identify the crystallographic b axis perpendicular to the crystal plane as the magnetic easy axis. Temperature-dependent resistivity measurements reveal metallic behavior with a distinct anomaly at TC = 14.3 K. Hall resistivity data indicate that electronlike carriers dominate, with a carrier concentration on the order of 1027m−3. The magnetic order is readily suppressed by a magnetic field of approximately 0.4 T applied along the easy b axis.

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Outline

Information

Phys. Rev. Materials 10, 084401– Published 5 August, 2026
  • Received 13 March 2026
  • Accepted 13 July 2026
Article part of CHORUS
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