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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 half-Heusler MTiSb (M = Fe, Co, Ni) compounds have been examined using the first-principles calculations with the full-potential linear augmented plane wave (FP-LAPW) method within the density functional theory. The electronic structures and magnetic properties of MTiSb (M = Fe, Co, Ni) are studied. It is found that the calculated lattice parameter is in good agreement with the theoretical values. Using the general gradient approximation (GGA), we observe that for the three compounds, the α phase is more stable than β and γ phases. CoTiSb is a semiconductor, NiTiSb is a metal, while the FeTiSb compound is a half-metallic, and the total magnetic moments are 0.00085, − 0.26074, and 0.99353 μ B, respectively, which is in agreement with the Slater-Pauling rule, Furthermore, the origin for the appearance of the half-metallic band gap in the FeTiSb compound was also discussed. [ABSTRACT FROM AUTHOR]

First-principles density functional theory (DFT) calculations with the generalized gradient approximation (GGA) have been performed to investigate electronic band structures and magnetic and half-metallic characteristic of TiCoAlSn ( x = 0, 0.25, 0.50, 0.75, 1). The optimized equilibrium lattice constants were found to be equal to 6.08 and 6.37 Å for TiCoAl and TiCoSn, respectively. These ternary Heusler compounds are found to be a complete half-metal with a total magnetic moment of 2 and 3 μ , respectively, which is in good compliance with the Slater-Pauling rule, M = Z − 18. The spin-polarized band structures and density of states (DOS) of the TiCoAlSn (0.25, 0.50, and 0.75) Heusler alloys confirm that they are half-metal due to the presence of the energy gap in the minority spin. Consequently, TiCoAlSn ( x = 0, 0.25, 0.50, 0.75, 1) alloys are predicted to be a promising candidate for the practical applications in spintronic devices. [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]

In this paper, ab initio electronic structure calculations are applied to study half-metallic properties of Heusler alloys XMnGe (X = Sc, Fe, Ni) with both CuHgTi-type and AlCuMn-type structures using first-principles calculations based on density functional theory (DFT). The exchange-correlation energy of electrons is described in the generalized gradient approximation (GGA). The results showed that for all compounds XMnGe, the AlCuMn-type structure is energetically more stable than CuHgTi-type structure at the equilibrium volume. The ScMnGe and FeMnGe are half-metallic in the CuHgTi- and AlCuMn-type structures, respectively; finally, NiMnGe have a metallic character in both CuHgTi- and AlCuMn-type structures. [ABSTRACT FROM AUTHOR]

The structural, half-metallic, and elastic characteristics of XZrAs (X = Cr, Mn, and V) half-Heusler compounds were theoretically calculated using the WIEN2k code. For the term of the potential exchange and correlation (XC), we calculated structural, electronic, and magnetic properties using the generalized gradient approximation (GGA). The type 1 arrangement in ferromagnetic (FM) phases is more energetically stable than other type arrangements in all compounds. The spin-up electrons of both XZrAs (X = Cr, Mn) half-Heusler compounds in the type III structure are semiconducting with energy gaps, whereas the spin-dn electrons are metallic. Research has also been done on the VZrAs compound, which exhibits metallic characteristics in both type I and type III structures. XZrAs (X = Cr, Mn, and V) half-Heusler compounds are elastically stable and ductile, according to calculated Cij elastic constants. Finally, at equilibrium lattice constants a = 6.1196 A° for MnZrAs and 6.142 A° for CrZrAs, real half-metal ferromagnetic materials (HMF) were produced from XZrAs (X = Cr, Mn) half-Heusler compounds within 3 µB and 2µB, respectively. [ABSTRACT FROM AUTHOR]