Abstract
The AIn5Te8 compounds (A = Cu, Ag, Au), charge balanced defect chalcopyrites, are characterized. Synchrotron powder diffraction shows that the Cu and Ag analogs are tetragonal to high precision at room temperature, with classic 158 (I-III5-VI8) defect chalcopyrite structures in space group I4¯2m. These materials display ordered vacancies but disordered cations. The degree of cation intermixing is more significant in the Cu case than in the Ag case. In contrast, AuIn5Te8, a previously unreported 158 defect chalcopyrite, exhibits a tetragonal P4¯2c structure with disordered vacancies and cations, displaying poorer crystallinity than the other two materials. The direct optical band gaps (Eg), determined from UV–vis absorption measurements, are estimated to be 0.94, 0.99, and 0.77 eV, respectively. Comparison to the corresponding sulfides and selenides for 158 and standard 112 (I-III-VI2) type chalcopyrites is reported where the data are available.
Original language | English (US) |
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Article number | 121752 |
Journal | Journal of Solid State Chemistry |
Volume | 292 |
DOIs | |
State | Published - Dec 2020 |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Ceramics and Composites
- Condensed Matter Physics
- Physical and Theoretical Chemistry
- Inorganic Chemistry
- Materials Chemistry
Keywords
- Defect chalcopyrite
- Optical band gap
- Rietveld refinement
- Synchrotron powder diffraction
- Telluride