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Using the first-principles full-potential linearized augmented-plane-wave method with the GGA-PBE approximations, we have explored the structural, elastic, electronic, and optical characteristics of Co2−xVxFeGe. Our investigation reveals that the compound Co1.25V0.75FeGe exhibits ideal half-metallic ferromagnetism. Additionally, the compound Co2−xVxFeGe exhibits different crystal structures depending on the value of x. At x = 0.25, it has a cubic structure with a space group of P-43 m. However, at x values of 0.50 and 0.75, it undergoes a transition to a tetragonal structure with respective space groups of P42/mcm N◦ (132) and P-42 m (111). In these tetragonal structures, the compound displays anisotropic mechanical stability. Moreover, as the concentration of V increases, the volume gradually increases. These properties are crucial in determining the material's suitability for use in optoelectronic devices. The electronic properties of most of the compounds displayed half-metallicity and 100% spin polarization, particularly for the composition x = 0.75. [ABSTRACT FROM AUTHOR]

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]

Density functional theory has been used to study the structural, elastic, electronic, magnetic and optical properties of Ti2FeSb Heusler alloy using generalised gradient approximation implemented through the WIEN2k code. The cubic structure of Ti2FeSb is mechanically stable in the F-43m space group and shows elastic anisotropic properties with ductile nature. Ti2FeSb shows spin gapless semiconductor behaviour along with an indirect energy band gap (EG) of 0.10 eV along the Г-Χ in majority spin (γ-spin) band above the Fermi energy level (EF) and 0.90 eV in the minority spin (δ-spin) band at EF. The total magnetic moment is 3 µB at optimized lattice constant (ao) 6.32 Å and follows the Slater–Pauling curve for inverse Heusler alloys. Robustness of this material with respect to change in the value of ao is evident in the constancy of magnetic moment along with retention of the half metallic nature within a lattice variation ±4% from equilibrium value of ao. Reflectivity, optical conductivity, dielectric function, absorption coefficient and energy loss have also been investigated as a function of incident energy for this alloy. [ABSTRACT FROM AUTHOR]

The structures and magnetic and electronic attributes of the Fen + 1@C32 and FenN@C32 (n = 1–3) clusters have been investigated by the PBE function. The results indicate that the Fe atoms prefer to occupy the center of a hexagonal C ring while the N atoms prefer to occupy the C–C bridge site. There is not enough space inside the C32 cages to embed larger Fen + 1 or FenN clusters by the binding energies. The FenN@C32 clusters are more structurally stable than the corresponding Fen + 1@C32 clusters by the embedding energies. The Fe@C32, Fe4@C32, N@C32 and Fe3N@C32 clusters are more kinetically stable than their neighbors by the HOMO-LUMO gaps. The spin polarization of the Fen + 1@C32 and FenN@C32 clusters is completely degraded to zero by the C32 coating. The N atoms for the FenN@C32 clusters accept electrons from the Fe and C atoms. [ABSTRACT FROM AUTHOR]

In this paper, we perform first-principles calculations of substituting Cobalt impurity into Indium Arsenide (InAs) graphene-like, and investigate the electronic, magnetic and optical properties of the resulting compound compared to the pure InAs graphene-like. The calculations are executed using the full-potential augmented plane wave method in the framework of the density-functional theory using the computational Wien2k. Looking into the band structure and density of states diagrams in the electronic discussion, it is found that the energy gap is reduced with doping Cobalt into InAs graphene-like. Moreover, in magnetic analysis, we conclude that by substituting Indium atoms with Cobalt, the InAs nano-sheets are transformed from non-magnetic semiconductors to semi-metals with a magnetic moment of about 4µB due to a strong spin–orbit effect between the electrons and the nuclei of Co atoms. This compound reaches a 100% spin polarization and turns to a half-metal which can have lots of applications in spintronics industry. [ABSTRACT FROM AUTHOR]

The first principles calculations are carried out to understand the half metallic and ferromagnetic properties of Fe2−xCoxTiSi (x = 0, 0.5, 1, 1.5, 2) full Heusler alloys. The stable structure is predicted as L21 structure (Cu2MnAl phase). The lattice constant value of Fe2−xCoxTiSi Heusler compounds increases as the value of x increases. These alloys exhibit half metallic ferromagnetism (except Fe2TiSi) with small spin flip gap at the minority spin state. At high pressure, semiconductor to metallic phase transition is observed in Fe2TiSi while half metallic to metallic phase transition is observed in Fe1.5Co0.5TiSi, Fe1.0 Co1.0TiSi, Fe0.5Co1.5TiSi and Co2TiSi. The spin polarization of these compounds (except Fe2TiSi) is 100%. Hence, these compounds are suitable for spin injection devices in spintronics. [ABSTRACT FROM AUTHOR]

In this study, structural, electronic and magnetic properties of non-transition metal-based binary compounds X Bi (X = Ba, Sr and Ca) in five different phases: rock salt, NiAs, wurtzite, zinc blende and CsCl, are investigated in order to find new sp magnetic materials used for real spintronic and other related applications. The calculations are performed by a developed full-potential augmented plane wave plus local orbitals (FP-L/APW + lo) method within the spin density functional theory. As exchange-correlation potential, we used the generalized gradient approximation of Perdew, Burke, and Ernzerhof (GGA-PBE) and the modified Becke-Johnson potential mBJ-GGA-PBE form. It is found that the magnetic moment in these compounds is mainly contributed by the spin-polarized p orbitals of Bi atoms. The WZ XBi are true half-metallic ferromagnet with opposite spin direction at Fermi energy having a magnetic moment of 2.00 μ B per formula unit. [ABSTRACT FROM AUTHOR]

In this study, we have explored the structural, electronic, and magnetic properties of V-doped zincblende MgSe and MgTe compounds using density functional calculations. The Wu-Cohen generalized gradient approximation is used for optimizing the structural properties, while the modified Becke and Johnson local (spin) density approximation functional has been employed to compute the electronic and magnetic properties. The spin dependent band structures, electronic density of state, and magnetic moments calculated for V-doped MgSe and MgTe semiconductors exhibit occurrence of 100 % spin polarization at the Fermi level which confirms stable half-metallic ferromagnetism in these materials. The spin-down gaps and the half-metallic gaps are analyzed in terms of V- 3d and Se-4 p (Te-5 p) hybridization, where it is observed that the V- 3dstates play a key role in generating spin polarization and the magnetic moment in these compounds. The exchange constants N αand N β have been calculated to demonstrate the effects resulting from exchange splitting process. Furthermore, spin-polarized charge density calculation is presented for elucidating the bonding nature, while pressure dependence of total magnetic moment for three concentrations of V-doped MgSe and MgTe are also discussed. [ABSTRACT FROM AUTHOR]