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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]

Using the first-principles density functional calculations, the structural, electronic and magnetic properties of the Fe 2 XAl (X=Cr, Mn, Ni) compounds in both the Hg 2 CuTi and Cu 2 MnAl-type structures were studied by the full-potential linearized augmented plane waves (FP-LAPW) method. The exchange and correlation potential is treated by the generalized-gradient approximation (GGA) where the results show that the Cu 2 MnAl-type structure is energetically more stable than the Hg 2 CuTi-type structure for the Fe 2 CrAl and Fe 2 MnAl compounds at the equilibrium volume. The full Heusler compounds Fe 2 XAl (X=Cr, Mn) are half-metallic in the Cu 2 MnAl-type structure. Fe 2 NiAl has a metallic character in both CuHg 2 Ti and AlCu 2 Mn-type structures. The total magnetic moments of the Fe 2 CrAl and Fe 2 MnAl compounds are 1.0 and 2.0 μ B , respectively, which are in agreement with the Slater–Pauling rule M tot =Z tot − 24. [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]

Using the full-potential linearized augmented plane-wave method of first-principles calculations of density functional theory, we have performed a systematic investigations on the structural, electronic, and magnetic properties related to the spintronic applications for gallium phosphide GaP doped with 3 d transition metal (TM) atoms such as vanadium (V), chromium (Cr), and manganese (Mn) as ternary GaGa TMP diluted magnetic semiconductors (DMSs) in zinc-blende phase at concentrations x = 0.0625, 0.125, and 0.25. The analysis of electronic and magnetic properties with various concentrations ( x) of TM revealed that GaGa VP at ( x = 0.0625, 0.125, and 0.25) and Ga TMP (TM = Cr and Mn) at ( x = 0.0625 and 0.125) are half-metallic ferromagnets (HMF) with spin polarization of 100 %. The HMF character destroyed for GaGaCrP and GaGaMnP at higher concentration x = 0.25 of Cr and Mn. The half-metallic gap increases with decreasing in concentration of impurity, and therefore, the GaGa TMP, GaGaCrP, and GaGaMnP DMSs at low concentrations appear to be better candidates for spintronic 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]

We investigate the structural, electronic, and magnetic properties of zinc-blende diluted magnetic semiconductors (DMS) Al TMN for transition metals (TM) = V, Cr, Mn, and Fe at x = 0.125 and 0.25, using first-principle calculations with the full-potential linearized augmented plane wave (FP-LAPW) method within the density functional theory and local spin-density approximation, in an aim to predict properties of Al TMN compounds. We have analysed the reliance of structural parameter values on the composition x in the range of x= 0.125−0.25. Results of calculated electronic structures reveal that Al TMN have stable ferromagnetic ground state and they are ideal half-metallic (HM) ferromagnetic at their equilibrium lattice constants. We have also studied the magnetic moment of Al TMN by increasing the concentration of TM atom; this is the most important source of the total magnetic moment in these alloys, while the contributions from Al, N, and interstitial moments are minor. [ABSTRACT FROM AUTHOR]

Abstract: First principles density functional calculations, using a full potential linearized augmented plane wave (FP-LAPW) method in local spin density approximation(LSDA), have been performed in order to investigate the structural, electronic and magnetic properties of In1−x TM x N(TM=Cr,Fe,Mn,V) in zinc-blende phase. Dependence of structural parameter values on the composition x have been analyzed in the x=0.25, x=0.50, and x=0.75, we found the existence of deviation from Vegard׳s law. Calculated electronic structure and the density of states of these alloys are discussed in terms of the contribution of TM 3d, N 2p, and In 3d states. The magnetic moment of In1−x TM x N has been studied by increasing the concentration of TM atom. The contribution of TM atom is the most important source of the total magnetic moment in these alloys, while it is minor in In and N. [Copyright &y& Elsevier]

In this paper, we present a theoretical study of structural, electronic and magnetic properties for zinc-blende GaTMN(TM = Cr, Fe, Mn, V) using the full-potential augmented plane wave (FP-APW) method with local-spin density approximation (LSDA). We have analysed the dependence of structural parameters values on the composition x in the range of x=0.25, x=0.50. Also, the role of p-d hybridisation is analysed by partial (PDOS) and total density of states (TDOS). The magnetic moment of GaTMN has been studied by increasing the concentration of TM atom. The TM atom is the most important source of the total magnetic moment in these alloys, while the contributions from Ga and N are minor. In addition our results verify the half-metallic ferromagnetic character of TM doped GaN. [ABSTRACT FROM AUTHOR]

We investigate the structural, electronic, and magnetic properties of (M = Fe, Mn)-based zinc blende diluted magnetic semiconductors (DMS) (Al, Ga, In)MN for ( x=0.0625,0.125,0.25), using first-principles calculations with the full-potential linearized augmented plane waves (FP-LAPW) method within the density functional theory and local spin-density approximation. The analysis of electronic structures and magnetic properties show that (Al, Ga, In)FeN at ( x=0.0625,0.125,0.25) are magnetic insulators, and InMnN at ( x=0.0625,0.125) are metallic in nature. On the other hand the (Al, Ga)MnN at ( x=0.0625,0.125,0.25) and InMnN are half-metallic ferromagnets with magnetic spin polarization of 100 %, where the ferromagnetic ground states result from a double-exchange mechanism, and these compounds are predicted to be good candidates for spintronic applications. [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]

The structural, electronic and magnetic properties of beryllium chalcogenides such as BeS, BeSe and BeTe doped with magnetic vanadium (V) impurity as ternary Be 1− x V x Z (Z = S, Se and Te) compounds in zinc blende phase have been performed at concentration x = 0.25, by employing first-principles calculations of full-potential linearized augmented plane-wave method within the framework of density functional theory. The electronic structures of Be 0.75 V 0.25 Z (Z = S, Se and Te) compounds revealed a half-metallic ferromagnetic character with 100% spin polarized that emerges this behavior results from the band gap of minority spin and metallic nature of majority spin due to a strong hybridization between 3 d (V) and p (S, Se and Te) states dominating at Fermi level. According to the results of magnetic properties calculations, the total magnetic moments of Be 0.75 V 0.25 Z (Z = S, Se and Te) are integers Bohr magneton of 3 μ B that confirms the half-metallic behavior of these compounds. Therefore, the Be 0.75 V 0.25 Z (Z = S, Se and Te) compounds seem to be potential candidates to explore half-metallic ferromagnetism property for near future applications in spintronics. [ABSTRACT FROM AUTHOR]