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Motivated by the experimental synthesis of bulk MnTe with rocksalt structure, we use the first-principles calculations to explore the structural, electronic, and magnetic properties of VTe in four different phases: rocksalt, zinc-blende, wurtzite, and ground-state NiAs. It is found that the ground-state NiAs phase is antiferromagnetic, but both the zinc-blende and wurtzite phases exhibit truly half-metallic ferromagnetism, and the rocksalt phase is a nearly half-metal. Importantly, the rocksalt phase is energetically more stable than the zinc-blende and wurtzite ones. We further reveal that there is an interesting transition from the nearly half-metallicity in bulk rocksalt VTe to the truly half-metallicity at the Te-terminated (111) surface, and the Te-terminated (111) surface is energetically more stable than the V-terminated (111) surface, which makes VTe with rocksalt structure promising candidate for spintronic applications. [ABSTRACT FROM AUTHOR]

Recent studies by Gao et al. [Phys. Rev. B 75, 174442 (2007)] indicate zinc-blende CaC, SrC, and BaC exhibit robust sp half-metallic ferromagnetism with Curie temperatures higher than room temperature. Here we further investigate the surface electronic and magnetic properties of CaC by using the first-principles full-potential linearized augmented plane-wave method. The (001) surfaces terminated with Ca and C, respectively, and the (110) surface terminated with both Ca and C are considered. We discuss the surface stabilities from the calculated relaxed surface energies. Electronic structure calculations indicate that the half-metallicity is destroyed for both the Ca- and C-terminated (001) surfaces; however, the (110) surface preserves the half-metallic characteristic of the bulk CaC. We further reveal that the atomic magnetic moments of the (001) surfaces are greatly different from the bulk values, but the difference of atomic magnetic moments between the (110) surface and the bulk CaC is very small. [ABSTRACT FROM AUTHOR]

We perform a first-principles study of electronic structure and magnetism of C-doped zinc-blende ZnO using the full-potential linearized augmented plane wave method. Results show that C-doped zinc-blende ZnO exhibits half-metallic ferromagnetism with a stable ferromagnetic ground state. The calculated magnetic moment of the 32-atom supercell containing one C dopant is 2.00 µB, and the C dopant contributes most. The calculated low formation energy suggests that C-doped zinc-blende ZnO is energetically stable. The hole-mediated double exchange mechanism can be used to explain the ferromagnetism in C-doped zinc-blende ZnO. [ABSTRACT FROM AUTHOR]

Abstract: The electronic and the magnetic properties of the molecule-based magnet [Co(μ 1,3-SCN)2(μ 1,6-dmpzdo)]n (where dmpzdo=2,5-dimethylpyrazine-1,4-dioxide) have been investigated using first-principles, namely density-functional theory (DFT) with the generalized gradient approximation (GGA) method and the full-potential linearized augmented plane-wave method (FP_LAPW). The total energy, the spin magnetic moments and the density of states (DOSs) were all calculated and spin distributions in ferromagnetic and anti-ferromagnetic (AFM) states of it have been obtained by the calculation. The electronic structure and magnetic coupling between cobalt ions along chain are discussed, and the calculations reveal that the compound [Co(μ 1,3-SCN)2(μ 1,6-dmpzdo)]n has a stable anti-ferromagnetic ground state, which is in good agreement with the experimental results. [Copyright &y& Elsevier]

Motivated by the experimental synthesis of bulk rocksalt MnS, MnSe, and MnTe, we show with first-principles calculations that among all transition-metal pnictides and chalcogenides with rocksalt structure CrTe, VPo, and CrPo are truly half-metallic ferromagnets, and both VTe and CrSe exhibit nearly half-metallicity. Importantly, for these five half-metallic compounds, the rocksalt phase is energetically more stable than the zinc-blende and wurtzite ones, and the total energy differences between the rocksalt and ground-state NiAs phases are very small (0.06-0.43 eV/f.u.) and comparable with that of experimental MnTe (0.24 eV/f.u.), thus like rocksalt manganese chalcogenides, these five rocksalt half-metals would be realized in the form of bulk or at list thin films for spintronic applications. In addition, we study the (111) surface properties of rocksalt CrPo and find both Cr- and Po-terminated (111) surfaces retain the bulk half-metallicity. We also reveal that the spin-orbit coupling has very weak effect on the half-metallicity of rocksalt CrSe, VTe, and CrTe, and the spin polarizations are still high for rocksalt VPo and CrPo although the spin-orbit coupling affects greatly their half-metallicities. [ABSTRACT FROM AUTHOR]

Recent studies showed that half-Heusler FeCrSe exhibits half-metallic ferromagnetism (Huang et al. [ 20 ]). In this paper, we investigate extensively the electronic, magnetic, and half-metallic properties of the half-Heusler alloy FeCrSe (111) and (001) surfaces and the interface with GaP (111) substrate by using the first-principles calculations within the density functional theory. The atomic density of states demonstrates that the half-me tallicity verified in the bulk FeCrSe is maintained at the CrSe-terminated (001) and Se-terminated (111) surfaces, but lost at both Cr- and Fe-terminated (111) surfaces and the Fe-terminated (001) surface. Alternatively, for the interface of FeCrSe/GaP (111), the bulk half-metallicity is destroyed at Se–P configuration while Se–Ga interface and subinterface show nearly 100% spin polarization. Moreover, the calculated interfacial adhesion energies exhibit that Se–Ga shape is more stable than the Se–P one. The calculated magnetic moments of Se, Ga at the Se–Ga (111) interface and P at the Se–P (111) interface increase with respect to the corresponding bulk values while the atomic magnetic moment of Se atom at the Se–P (111) interface decreases. We also notice that the magnetic moments of subinterface Fe at both Se–Ga and Se–P (111) interfaces decrease compared to the bulk values. [ABSTRACT FROM AUTHOR]

Highlights: [•] The half-metallicity is preserved at the (001) and Ba (C)-terminated (111) surfaces. [•] The surface magnetic moments are increased (decreased) at the C(Ba)-terminated (111) surface. [•] Interfacial studies appear that the half-metallicity of bulk RS BaC is destroyed for all possible configurations. [•] The atoms of interfacial in the semiconductor slabs change from nonmagnetic to magnetic. [Copyright &y& Elsevier]

Abstract: In this work, we have probed the structural, electronic, and magnetic properties of the (111) surface of rocksalt (RS) VPo. The first-principles full-potential linearized augmented plane-wave method is used. Bulk VPo is found to be a half-metallic ferromagnet at equilibrium lattice constant (0.59nm) with a total spin magnetic moment of 3.0μB per formula unit. At the same equilibrium lattice constant, the V-terminated (111) surface preserves the half-metallic characteristics of the bulk VPo, however, the surface states destroy the gap in the minority spin band of the Po-terminated (111) surface. We also discuss the surface stability. [Copyright &y& Elsevier]

Abstract: The electronic and magnetic properties of the full-Heusler compound Co2MnP were studied using the full-potential augmented plane wave plus the local orbitals method within the density functional theory. Spin-polarized calculations predicted that the full-Heusler compound Co2MnP is a half-metallic ferromagnet with a magnetic moment of per formula unit and a spin-flip gap of 0.60 eV at its equilibrium lattice constant. The half-metallic ferromagnetism of the full-Heusler compound Co2MnP can be retained even when the lattice constant is changed by 1.2%. [ABSTRACT FROM AUTHOR]