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Register a new userAb initio study of noncentrosymmetric transition-metal monogermanide B20-RhGe synthesized at high temperature and pressure
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Added by
Nikolay Chtchelkatchev
Publication date
2019
fields
Physics
and research's language is
English
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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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