Structural stability, electronic and thermoelectric properties of ruthenium silicide

Abstract

The structural phase transition, electronic and transport properties of RuSi intermetallic compound has been studied using density functional theory (DFT). The pressure induced phase transition from B20 to B2 phase is observed at 6.4 GPa and compared with other theoretical results. The calculated ground state, electronic and transport properties are in good agreement with the previously reported results. The stability of RuSi at 0 and high pressure is also confirmed by phonon dispersion curve [see supplementary information].The band structure and density of states show that RuSi is metallic in B2 phase while semiconductor in B20 phase with indirect band gap of 0.34 eV. We have also calculated the transport properties of RuSi in terms of electrical conductivity (σ/τ), electronic thermal conductivity (κe/τ), Seebeck coefficient (S) and power factor (S2σ/τ) in B20 phase. Our results show that RuSi is p-type semiconductor and is in good agreement with the experimental data. Bonding nature is discussed using Fermi surface, band structure and charge density difference plots.