First principles analysis of the half-metallic ferromagnetism, elastic and thermodynamic properties of equiatomic quaternary Heusler compound CoCrRhSi

Highlights: • CoCrRhSi can be synthesized in experiments with proven structural and dynamical stability. • CoCrRhSi is half-metallic with ferromagnetic gap of 1.125 eV. • CoCrRhSi magnetism is derived mainly from Cr and Co 3d orbital. • CoCrRhSi is mechanically stable and elastically ductile. • The CoCrRhSi hardness increases with pressure and decreases with temperature. In this paper, the structural, electronic, magnetic, elastic, and thermodynamic properties of the new equiatomic quaternary Heusler (EQH) compound CoCrRhSi are theoretically investigated. The ferromagnetic state is found to be energetically favorable. CoCrRhSi is a half-metallic compound exhibiting the metallic spin-up channel and a semiconducting behavior with an indirect band gap of 1.125 eV in the spin-dn channel. Moreover, the magnetic properties of this material satisfy the Slater–Pauling rule with a total magnetic moment of 4 ${\mu }_B$. The strain effect investigation indicates that the half-metallicity is more stable under the lattice compression than the tension. Elastic properties results indicate the mechanical stability and elastic ductility of this compound. Finally, with the aim of providing thermodynamic characteristics of CoCrRhSi compound under different working conditions of pressure and temperature, its thermodynamic parameters including volume, bulk modulus, thermal expansion coefficient, heat capacity and Debye temperature are determined and discussed in detail.