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The first-principle calculations of density functional theory were used to study the structural, electronic, magnetic, mechanic, and half-metallic behavior of Y2MnZ (Z = Al, Ga, In) within the spin generalized gradient approximation. These compounds can be experimentally synthesized due to their negative values of the calculated formation energies. Our calculations indicate that they are more stable in Cu2MnAl-type structure. The Hg2CuTi-type structure displays half-metallic characteristic with 100% spin polarization at the Fermi level. The value of calculated magnetic moment has an integer value of 2μB for Y2MnZ (Z = Al, Ga, In) in the Hg2CuTi-type structure which well matches with magnetic moments predicted from Slater–Pauling rule. Therefore, the Y2MnZ (Z = Al, Ga, In) in the Hg2CuTi-type structure is predicted to be a candidate for possible spintronics applications. [ABSTRACT FROM AUTHOR]

The structural, electronic, and magnetic properties of the full-Heusler compounds CoMnZ ( Z = Al, Ge, Si, Ga) have been investigated using the first-principles calculations with the full-potential linear-augmented plane wave method within the density functional theory. The electronic structures and magnetic properties of the CoMnZ ( Z = Al, Ge, Si, Ga) compounds with both HgCuTi- and CuMnAl-type structures are studied. It is found that the calculated lattice constants are in good agreement with the theoretical values. Using the general gradient approximation, we observe that the CuMnAl-type structure is more stable than the HgCuTi type. The CoMnZ ( Z = Al, Ge, Si, Ga) compounds were half-metallic ferromagnets in the CuMnAl-type structure. The total magnetic moments of the CoMnZ ( Z = Al, Ge, Si, Ga) compounds in the CuMnAl-type structure were 4, 5, 5, and 4 μ respectively, which is in agreement with the Slater-Pauling rule, m = N−24 Furthermore, the origin for the appearance of the half-metallic band gap in the CoMnZ compound was also discussed which shows them to be promising materials for possible spintronics applications. [ABSTRACT FROM AUTHOR]

We investigate the structural, electronic and magnetic properties of the full Heusler compounds Mn2YSn (Y=Mo, Nb, Zr) by first-principles density functional theory using the generalized gradient approximation. It is found that the calculated lattice constants are in good agreement with the theoretical values. We observe that the Cu2MnAl-type structure is more stable than the Hg2CuTi type. The calculated total magnetic moments of Mn2NbSn and Mn2ZrSn are 1/n; and 2/n; at the equilibrium lattice constant of 6.18 and 6.31, respectively, for the Cu2MnAl-type structure. Mn2MoSn have a metallic character in both Hg2CuTi and Cu2MnAl type structures. Thetotal spin magneticmoment obeys the Slater-Pauling rule. Half-metal exhibits 100% spin polarization at the Fermi level. Thus, these alloys are promising magnetic candidates in spintronic devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Based on DFT calculations, the XFeGe (X = Co, Cr, Ni) half Heusler alloys were investigated. • Half metallic behavior is explained via spin polarization results. • Magnetic and electronic properties for the XFeGe (X = Co, Cr, Ni) were studied. • The calculated elastic constants for the three compounds verified the mechanical stability criteria for cubic systems. The structural, electronic, magnetic and thermodynamic properties of XFeGe (X = Co, Cr, Ni) half Heusler compounds are studied using first-principles calculation within density functional theory in five different atomic configurations. For each configuration, their optimized lattice constants are determined. It showed that the configuration of type 3 is energetically the most stable. From the spin-polarized band structure and density of states, it is found that CoFeGe alloy exhibits a half-metallic character with integer magnetic moments of 3.00μ B per formula unit at their equilibrium volume, whereas NiFeGe and CrFeGe exhibit a metallic character. These results indicate that the magnetic moment mainly originates from the Fe atoms. The calculated equilibrium volume for the three compounds CoFeGe, CrFeGe, and NiFeGe at various temperatures is predicted. The heat capacity at constant volumeC V has been calculated as a function of temperature and pressure. Additionally, the calculated elastic constants for the three compounds confirm the mechanical stability criteria for cubic systems. [ABSTRACT FROM AUTHOR]