Low-Temperature Structural Phase Transitions in Thermoelectric Tetrahedrite, Cu12Sb4S13, and Tennantite, Cu12As4S13

Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaperJournal articleResearchpeer-review

DOI

  • Venkatesha R. Hathwar
  • Atsushi Nakamura, Univ Tsukuba, University of Tsukuba, Fac Pure & Appl Sci, Grad Sch
  • ,
  • Hidetaka Kasai, Univ Tsukuba, University of Tsukuba, Fac Pure & Appl Sci, Div Phys
  • ,
  • Koichiro Suekuni, Kyushu Univ, Kyushu University, Interdisciplinary Grad Sch Engn Sci, Dept Appl Sci Elect & Mat
  • ,
  • Hiromi I. Tanaka, Hiroshima Univ, Hiroshima University, Grad Sch Adv Sci Matter, Dept Quantum Matter
  • ,
  • Toshiro Takabatake, Hiroshima Univ, Hiroshima University, Grad Sch Adv Sci Matter, Dept Quantum Matter
  • ,
  • Bo B. Iversen
  • Eiji Nishibori, Univ Tsukuba, University of Tsukuba, Fac Pure & Appl Sci, Grad Sch

Tetrahedrite (Cu12Sb4S13) and tennantite (Cu12As4S13) crystallize in isomorphous cubic structures (I (4) over bar 3m) at room temperature and exhibit phase transitions at 85 and 124 K, respectively. We have investigated how the crystal structures change through the phase transitions using single crystal synchrotron X-ray diffraction data. The low-temperature structure of Cu12Sb4S13 belongs to the I (4) over bar 2m space group, which is described by the 2a x 2a x 2c supercell. The distortion of S(2)Cu(2)(6) octahedra is found to be responsible for the structural transformation. In contrast, the structure of Cu12As4S13 preserves its cubic symmetry and periodicity below the transition temperature. The low-temperature structure is characterized by positional disorder of S(1) and As(1) atoms along with a significant change in the occupancy of disordered sites of the Cu(2) atom. Besides distinct low-temperature structures for Cu12Sb4S13 and Cu12As4S13, the structural phase transition is further accompanied by negative thermal expansion of lattices (per formula unit) in both compounds.

Original languageEnglish
JournalCrystal Growth & Design
Volume19
Issue7
Pages (from-to)3979-3988
Number of pages10
ISSN1528-7483
DOIs
Publication statusPublished - Jul 2019

    Research areas

  • NEGATIVE THERMAL-EXPANSION, ZRW2O8

See relations at Aarhus University Citationformats

ID: 162633117