First-principles study of structural, electronic, and magnetic properties of Mn4X Ge3 (X = Fe, Co, Ni)

In order to search for promising candidates for spintronic applications, this paper systematically studies three ternary compounds based on Mn5Ge3 by using a full-potential linearized augmented plane wave method within the density functional theory. Through structure optimization and electronic structure calculations, it finds that Mn4FeGe3 and Mn4CoGe3 have much higher spin-polarization than original intermetallic compound Mn5Ge3, although the spin polarization of Mn4NiGe3 is lower than that of Mn5Ge3. The calculated result is in agreement with experiment in the case of Mn4FeGe3. Both of them can be taken as promising candidates for spintronics applications because of their high spin-polarization and compatibility with semiconductors. (condensed matter: structure, thermal and mechanical properties)