Universal Connection of magnetic exchange and structural behavior under pressure in chromium spinels.

ORAL

Abstract

We have conducted high-pressure x-ray diffraction studies on the MnCr2O4 and NiCr2O4 spinels at room temperature [1]. Both compounds undergo pressure-induced structural transitions into diverse tetragonal modifications. Based on these experimental observations and our ab initio calculations, we show that the Cr-oxide spinels with magnetic A2+ cations (A2+ = Mn, Fe, Co, Ni) follow a similar trend as their chalcogenide counterparts with nonmagnetic A2+ ions, i.e., the transition pressure is proportionally related with the magnitude of the Cr-Cr magnetic exchange interactions. Therefore, we reach the conclusion that the Cr-Cr magnetic exchange interactions alone suffice to account for the high-pressure behavior of these systems. Our results clearly depict the close relationship between the structural and magnetic degrees of freedom in Cr-bearing spinels.

[1] I. Efthimiopoulos, I. Khatri, Z. T. Y. Liu, S. V. Khare, P. Sarin, V. Tsurkan, A. Loidl,
Physical Review B 97 (2018), 184435.

*We would like to thank several funding agencies in the countries of the authors.

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Presenters

  • Indiras Khatri

    • University of Augsburg
    • The University of Toledo
    • Univ of Toledo

Authors

  • Ilias Efthimiopoulos

    • Oakland University

  • Indiras Khatri

    • University of Augsburg
    • The University of Toledo
    • Univ of Toledo

  • Z. T. Y. T. Y. Liu

    • The University of Toledo

  • Sanjay V Khare

    • The University of Toledo

  • Pankaj Sarin

    • Oklahoma state university

  • Indiras Khatri

    • University of Augsburg
    • The University of Toledo
    • Univ of Toledo

  • Indiras Khatri

    • University of Augsburg
    • The University of Toledo
    • Univ of Toledo

  • Zhang Dongzhou

    • University of Hawaii at Monoa

  • Yuejian Wang

    • Oakland University