Structural, electronic, elastic, and thermodynamic properties of the spin-gapless semiconducting Mn2CoAl inverse Heusler alloy under pressure

摘要

Structural, electronic, elastic, and thermodynamic properties of the spin-gapless semiconducting (SGS) Mn2CoAl inverse Heusler alloy under pressure are investigated by using the density functional theory (DFT) and the quasi-harmonic Debye model. The calculated equilibrium lattice parameter and SGS behavior agree with the experimental and other theoretical data. It is only when the external pressure is beyond about 25 GPa that the SGS behavior and dynamical stability are destroyed, indicating that the SGS behavior is robust against pressure less than 25 GPa in everyday experiments. Furthermore, the thermal properties, including bulk modulus B, thermal expansivity alpha, Gruneisen parameter gamma, heat capacity C-V, and Debye temperature Theta(D) of Mn2CoAl are evaluated up to 25 GPa. These thermodynamic properties will be referenced in the further experiments.