Structural, elastic, electronic, magnetic and thermoelectric properties of new quaternary Heusler compounds CoZrMnX (X=Al, Ga, Ge, In)

TL;DR

This study uses first principles calculations to explore the structural, electronic, magnetic, and thermoelectric properties of new quaternary Heusler compounds CoZrMnX (X=Al, Ga, Ge, In), revealing their stability, electronic behavior, and potential for thermoelectric applications.

Contribution

The paper provides the first comprehensive theoretical analysis of these specific CoZrMnX Heusler compounds, including stability, electronic, magnetic, and thermoelectric properties.

Findings

All compounds are structurally stable in Type(I) structure.

CoZrMnAl is nearly half-metallic; CoZrMnGa and CoZrMnIn are metallic; CoZrMnGe is a narrow bandgap semiconductor.

CoZrMnAl, CoZrMnGa, and CoZrMnIn are ferromagnetic; CoZrMnGe is non-magnetic.

Abstract

We have performed a comprehensive set of first principles calculations to study the structural, elastic, electronic, magnetic and transport properties of new quaternary Heusler compounds CoZrMnX (X =Al, Ga, Ge, In). The results showed that all the quaternary Heusler compounds were stable in Type(I) structure. CoZrMnX are elastically stable and relatively hard materials. CoZrMnAl, CoZrMnGa, and CoZrMnIn are found to be ductile and CoZrMnGe is brittle in nature. The calculated Debye temperatures of all compounds are relatively high. The electronic structure calculations reveal that CoZrMnAl is nearly half metallic, CoZrMnGa and CoZrMnIn are metallic, and CoZrMnGe is a narrow indirect bandgap semiconductor. The calculated magnetic properties implies that CoZrMnAl, CoZrMnGa, and CoZrMnIn are ferromagnetic while CoZrMnGe is non-magnetic material. The CoZrMnAl is highly spin-polarized (96%) and CoZrMnGe is non-spin-polarized. Seebeck coefficent (S) in CoZrMnGe is relatively high (-106 {\mu}V/K at 650K) due to its semiconducting nature. The calculated thermoelectric figure of merit CoZrMnGe is 0.1 at 600K and for CoZrMnIn it is also 0.1 at 900 K. We hope our interesting results will inspire experimentalist to synthesis the new quaternary Heusler compounds CoZrMnX (X =Al, Ga, Ge, In).