Topological Phase Transition and Lattice Dynamical Properties of Half‐Heusler XPtBi (X = Gd, Nd)

Abstract

Topological materials ranging from insulator to semimetals depending upon the band degeneracies are attracting the interest of researchers nowadays due to their fascinating physical properties. Among these, half‐Heuslers GdPtBi and NdPtBi have been theoretically predicted to be topological semimetals. The structural stability and electronic properties of the proposed compounds are computed within the framework of density functional theory. The results of structural optimization show that the ferromagnetic phase of the considered compounds is more stable than nonmagnetic phase. Moreover, the inclusion of magnetization in both these compounds generates Weyl nodes in the compounds. The dynamical stability of XPtBi (X = Gd and Nd) is confirmed by the computed vibrational properties of the compounds. Further, the thermodynamical parameters such as specific heat, entropy, Debye's temperature, and thermal expansion have been investigated by applying Debye's framework based on quasi‐harmonic approximation in the temperature range from 0 to 1000 K and pressure range 0–5 GPa. This work will encourage experimentalists to further study these materials for practical utilization.