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arXiv · 1906.07278

Ab initio study of noncentrosymmetric transition-metal monogermanide B20-RhGe synthesized at high temperature and pressure

N. M. Chtchelkatchev·M. V. Magnitskaya·A. V. Tsvyashchenko
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Abstract

We present ab initio density-functional study of the noncentrosymmetric B20-type phase of RhGe, which is not found in nature and can be synthesized only at extreme pressures and temperatures. The structural, thermodynamic, electronic, lattice-dynamical, and transport properties of B20-RhGe are calculated, and their evolution with increasing pressure is traced. The temperature dependence of the charge and heat transport properties is evaluated within the semi-classical Boltzmann approach. Using the quasi-harmonic approximation, we determine the range of pressures and temperatures, in which B20-RhGe is stable, and make recommendations for optimizing the synthesis conditions in order to reduce the number of defects that occur in a sample during solidification.

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N. M. Chtchelkatchev, M. V. Magnitskaya, A. V. Tsvyashchenko. 2019-06-17. Ab initio study of noncentrosymmetric transition-metal monogermanide B20-RhGe synthesized at high temperature and pressure. https://doi.org/10.1140/epjst%2Fe2019-900114-y

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