Physical properties of Si2Ge and SiGe2 in hexagonal symmetry: First-principles calculations
| Autor: | Ying-bo Zhao, Shi-xuan Lin, Qing-yang Fan, Qi-dong Zhang |
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| Rok vydání: | 2022 |
| Předmět: | |
| Zdroj: | Chinese Journal of Chemical Physics. 35:551-561 |
| ISSN: | 2327-2244 1674-0068 |
| Popis: | We predict two novel group 14 element alloys Si2Ge and SiGe2 in P6222 phase in this work through first-principles calculations. The structures, stability, elastic anisotropy, electronic and thermodynamic properties of these two proposed alloys are investigated systematically. The proposed P6222-Si2Ge and P6222-SiGe2 have a hexagonal symmetry structure, and the phonon dispersion spectra and elastic constants indicate that these two alloys are dynamically and mechanically stable at ambient pressure. The elastic anisotropy properties of P6222-Si2Ge and P6222-SiGe2 are examined elaborately by illustrating the surface constructions of Young’s modulus, the contour surfaces of shear modulus, and the directional dependence of Poisson’s ratio; the differences with their corresponding group 14 element allotropes P6222-Si3 and P6222-Ge3 are also discussed and compared. Moreover, the Debye temperature and sound velocities are analyzed to study the thermodynamic properties of the proposed P6222-Si2Ge and P6222-SiGe2. |
| Databáze: | OpenAIRE |
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