First Principles Study of Fe based Full Heusler Alloy

Kumari Seema, Mandeep Kaur, Ranjan Kumar

Abstract


The electronic structure of Fe-based quaternary Heusler compounds Fe2CoZ (Z=Ga, Ge) is calculated by first-principles density functional theory. Structural optimization is performed for two possible structures: Hg2CuTi-type and Cu2MnAl-type structures of Fe2CoZ. We found that Hg2CuTi-type structure is energetically more favorable than Cu2MnAl-type structure. The calculated equilibrium lattice constant is 5.812Å and 5.75Å respectively for Ga and Ge based alloy. The calculations reveal that Fe2CoGa material exhibit 100% spin-polarization whereas Fe2CoGe has 62% spin-polarization. The value of magnetic moment for Fe2CoGa and Fe2CoGe is 5.72mB, 4.96mB respectively

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