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Abstract Previous band structure calculations predicted Ag3AuSe2to be a semiconductor with a band gap of approximately 1 eV. Here, we report single crystal growth of Ag3AuSe2and its transport and optical properties. Single crystals of Ag3AuSe2were synthesized by slow‐cooling from the melt, and grain sizes were confirmed to be greater than 2 mm using electron backscatter diffraction. Optical and transport measurements reveal that Ag3AuSe2is a highly resistive semiconductor with a band gap and activation energy around 0.3 eV. Our first‐principles calculations show that the experimentally determined band gap lies between the predicted band gaps from GGA and hybrid functionals. We predict band inversion to be possible by applying tensile strain. The sensitivity of the gap to Ag/Au ordering, chemical substitution, and heat treatment merit further investigation.
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Stability, electronic, and optical properties of two‐dimensional phosphoborane
Abstract The structure and properties of two‐dimensional phosphoborane sheets were computationally investigated using Density Functional Theory calculations. The calculated phonon spectrum and band structure point to dynamic stability and allowed characterization of the predicted two‐dimensional material as a direct‐gap semiconductor with a band gap of ~1.5 eV. The calculation of the optical properties showed that the two‐dimensional material has a relatively small absorptivity coefficient. The parameters of the mechanical properties characterize the two‐dimensional phosphoborane as a relatively soft material, similar to the monolayer of MoS2. Assessment of thermal stability by the method of molecular dynamics indicates sufficient stability of the predicted material, which makes it possible to observe it experimentally.
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- Award ID(s):
- 1664379
- PAR ID:
- 10457475
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Computational Chemistry
- Volume:
- 41
- Issue:
- 15
- ISSN:
- 0192-8651
- Page Range / eLocation ID:
- p. 1456-1463
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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