Electronic, phonon and thermoelectric properties of MnCrX (X = As, P, Sb) half Heusler alloys: a DFT study

First principles investigations have been carried out for half-Heusler alloys MnCrX (X = P, As, Sb). The electronic band structures and density of states are computed for under study alloys. Reststrahlen bands are explained through the phonon dispersion curve calculated using Quantum ESPRESSO. The positive phonon frequencies in full zone ascertain the dynamic stability of all these under-study alloys. MnCrP exhibits a larger value of the Reststrahlen band than the other two and is an important candidate in Far Infra-Red spectroscopy applications. Moreover, the thermoelectric coefficients as a function of temperature have been studied using the Boltzmann transport equation. Half Heusler alloys have not yet explored for these properties. The power factor of MnCrP is the highest amongst these studied materials.