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

摘要

We have performed a comprehensive set of first principles calculations tostudy the structural, elastic, electronic, magnetic and transport properties ofnew quaternary Heusler compounds CoZrMnX (X =Al, Ga, Ge, In). The resultsshowed 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 isbrittle in nature. The calculated Debye temperatures of all compounds arerelatively high. The electronic structure calculations reveal that CoZrMnAl isnearly half metallic, CoZrMnGa and CoZrMnIn are metallic, and CoZrMnGe is anarrow indirect bandgap semiconductor. The calculated magnetic propertiesimplies that CoZrMnAl, CoZrMnGa, and CoZrMnIn are ferromagnetic while CoZrMnGeis non-magnetic material. The CoZrMnAl is highly spin-polarized (96%) andCoZrMnGe is non-spin-polarized. Seebeck coefficent (S) in CoZrMnGe isrelatively high (-106 {\mu}V/K at 650K) due to its semiconducting nature. Thecalculated thermoelectric figure of merit CoZrMnGe is 0.1 at 600K and forCoZrMnIn it is also 0.1 at 900 K. We hope our interesting results will inspireexperimentalist to synthesis the new quaternary Heusler compounds CoZrMnX (X=Al, Ga, Ge, In).