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The structural, electronic and magnetic properties of half-Heusler compounds XVSb (X = Fe, Co and Ni) are investigated by using the density functional theory with generalized gradient approximation (GGA), and Tran-Blaha modified Becke-Johnson (TB-mBJ) exchange potential approximation. It is found that the half-metallic gaps are generally reasonably widened by mBJ as compared to the GGAapproximation. The magnetic proprieties of XVSb (X = Fe, Co and Ni) are well defined within mBJ with an exact integer value of magnetic moment. The band gaps given by TB-mBJ are in good agreement with the available theoretical data. The FeVSb exhibits a semiconductor nature. The CoVSb and NiVSb present half-metallic behaviour with total magnetic moment of and 2B in good agreement with Slater-Pauling rule. These alloys seem to be a potential candidate of 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]

The structural, electronic as well as the magnetic properties of the Co2CrX (XAl, Ga and In) full-Heusler alloy have been studied using first-principles calculations performed in the framework of density functional theory (DFT) within the generalized gradient approximation (GGA). It was taken into account both possible L21 structures (i.e. Hg2CuTi- and Cu2MnAl-type). Basically, for all compounds, the Cu2MnAl-type structure is energetically more stable than Hg2CuTi-type structure at the equilibrium volume. The electronic structure calculations for Co2CrAl reveal that half-metallic (HM) character in Cu2MnAl-type structure, Co2CrGa show nearly HM behavior and Co2CrIn has a metallic character. The predicted total magnetic moment is for Co2CrX (XAl, Ga) which is in good convergence with the Slater-Pauling (SP) rule. [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]

In this paper, we use the 1rst-principles calculations based on the density functional theory to investigate structural, electronic and magnetic properties of Fe2YSn with (Y = Mn, Ti and V). The generalized gradient approximation (GGA) method is used for calculations. The Cu2MnAl type structure is energetically more stable than the Hg2CuTi type structure. The negative formation energy is shown as the evidence of thermodynamic stability of the alloy. The calculated total spin moment is found as 3µB and 0µB at the equilibrium lattice constant for Fe2MnSn and Fe2TiSn respectively, which agrees with the Slater-Pauling rule of Mt = Zt -24. The study of electronic and magnetic properties proves that Fe2MnSn and Fe2TiSn full-Heusler alloys are complete half-metallic ferromagnetic materials. [ABSTRACT FROM AUTHOR]