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In this paper, we present the first principle calculation of the different properties of the full Heusler compounds Cd2LaB, Cd2PrB, and Cd2CeB. Our calculations are based on density functional theory, using the full potential muffin-tin linear orbital method implemented in the LmtART code. For the determination of the exchange and correlation potential, we used the local density approximation and local spin density approximation. The elastic constants are also calculated. The total magnetic moment of Cd2LaB, Cd2PrB, and Cd2CeB using local spin density approximation are 3.334, 3.482, and 3.473 μB at ambient pressure, respectively. We also present the thermal effects using the quasi-harmonic Debye model, in which the vibrations of the network are taken into account. The effects of temperature and pressure on structural parameters, heat capacity, entropy, coefficient of thermal expansion, and the Debye temperatures are determined for unbalanced Gibbs functions. [ABSTRACT FROM AUTHOR]

The interaction between a photon and a material particle (electron and atom) is considered in a reference system moving at the speed of light in vector-potential space. Based on Noether's theorem it is shown that in vector-potential space the volumetric density of the photon energy, its velocity, and the ring current density of a material particle are retained. Based on solution of the Schrodinger equation for a photon and an electron interacting in vector-potential space, it is shown that during the interaction the electron should represent a quantum oscillator with a discrete set of energies. Electron fluctuations or Dirac's electron jitter occur at the speed of light. The problem of the appearance of the magnetic moment (spin) of an electron in vector-potential space is considered. The conditions of the quantization of atomic currents in vector-potential space and also Heisenberg's uncertainty principle in this space are presented. The Lamb frequency shift in the vector-potential space is found. A multiphoton system in the vector-potential space is investigated. [ABSTRACT FROM AUTHOR]

The modification and tailoring characteristics of nanostructured materials are of great interest due to controllable and unusual inherent properties in such materials. A simple spray pyrolysis technique was used to prepare pure and La-doped ZnO films. The influence of La concentration (0, 0.33, 0.45, 0.66, 0.92 and 1.04 at. %) on the structural, optical, and magnetic properties of ZnO was investigated. The exact nominal compositions of the prepared films were determined from the field emission scanning electron microscope occupied with EDX. X-ray diffraction confirmed that the samples possessed single-phase hexagonal wurtzite structure. The main crystal size was decreased from 315.50 Å to 229.04 Å depending on La dopant concentration. This decrease is due to the small ionic radius of Zn ions in compared to La ions. The band gap values were found to be depend strongly on La3+ ion content. Introducing La into ZnO induces a clear magnetic moment without any distortion in the geometrical symmetry, it also reveals the ferromagnetic coupling. The saturation magnetic moment of 1.04 at.% La-doped ZnO shows the highest value of 0.014 emu, which is ∼23 times higher than pure ZnO sample. The obtained results were discussed and compared with other literature data and showed an acceptable agreement. • Pure and La doped ZnO thin films were synthesized in hexagonal phase. • Band gap values depended strongly on the La doping ratio. • La doping induced ferromagnetism in the paramagnetic ZnO. [ABSTRACT FROM AUTHOR]

The full potential linearized augmented plane wave method (FLAPW) including the spin-orbit coupling has been used to study the structural, electronic and magnetic properties of GdCo5 compound. The calculations were performed within the local spin density approximation (LSDA) as well as Coulomb corrected LSDA + U approach. The study revealed that the LSDA + U method gave a better representation of the band structure, density of states and magnetic moments than LSDA. It was found that the spin magnetic moment of Co (2c) and Co (3g) atoms in the studied compound is smaller compared to the one in bulk Co. The optical and magneto-optical properties and the magneto-optical Kerr effect have also been investigated. [ABSTRACT FROM AUTHOR]

Nickel-substituted copper oxide nanoparticles at various concentrations were synthesized by the microwave irradiation technique. The consequence of nickel doping on crystal structure, optical properties, and magnetic properties was examined by means of X-ray diffractometer, ultraviolet-visible spectrometer, Fourier transform infrared (FT-IR) spectrometer, transmission electron microscope, and vibrating sample magnetometer (VSM). X-ray diffraction analysis shows that the samples are monoclinic and their crystallite size varies from 25 nm to 42 nm, and lattice constant significantly increases with nickel concentration. Additional increase of nickel content (7%) decreases the lattice constant. TEM micrograph witnessed that the prepared nanoparticles were sphere-shaped and the particle distribution is in the range between 20 and 40 nm. Bandgap measurement reveals that both undoped and nickel-doped copper oxides are direct bandgap semiconductor materials with bandgaps of 3.21 and 3.10 eV, respectively, FT-IR spectra of the synthesized samples confirmed the nickel doping. VSM studies confirmed the ferromagnetic behavior of the synthesized samples at room temperature. The results revealed that the nickel-doped copper oxide nanoparticles synthesized via the microwave irradiation method exhibit better magnetic properties than the undoped copper oxide. [ABSTRACT FROM AUTHOR]

A method for calculation of the ground-state magnetic moment, effective spin gyromagnetic factors and rotational decoupling parameter of the K = 1 / 2 states in deformed odd-mass nuclei has been described by using the concept of the Quasiparticle Phonon Nuclear Model (QPNM). The model includes a Woods-Saxon potential as a mean field with pairing correlations and the residual separable spin-spin force in both isovector and isoscalar channels. The method has been employed to investigate K = 1 / 2 ground-state magnetic properties of 169Er, 167,169Tm, and 171Yb nuclei, as an example. It has been shown that two different quenched spin gyromagnetic factors, i.e., g s z (eff.) and g s + (eff.) have a significant effect on the magnetic properties of K = 1 / 2 states in odd-mass nuclei. Whereas the first one is occurred due to the interaction between the valence nucleon and I π K = 1 + 0 excitations of the core, second one is associated with the coupling of the valence nucleon to I π K = 1 + 1 excitations of the core. The observed magnetic moments and the phenomenological value of g s z (eff.) for considered odd-mass nuclei have been reproduced very well by the calculations. The role of the isoscalar and isovector interactions on the magnetic properties of K = 1 / 2 states in these nuclei has been also discussed. [ABSTRACT FROM AUTHOR]

The 5d transition metal oxide Sr2IrO4 has attracted much interest in the high-temperature superconductivity community since it highly resembles the cuprate superconductor in crystal and electronic structures. Here, we report on the transport and magnetic properties of Zn-doped Sr2IrO4. It is found that the energy gap of Sr2IrO4 is rapidly decreased with a small amount of Zn doping. Consequently, the electrical conductivity is significantly enhanced. The present work could serve as the prerequisite stage in exploring the possible superconductivity of the Sr2IrO4 compound. [ABSTRACT FROM AUTHOR]

The 5d transition metal oxide Sr2IrO4 has attracted much interest in the high-temperature superconductivity community since it highly resembles the cuprate superconductor in crystal and electronic structures. Here, we report on the transport and magnetic properties of Zn-doped Sr2IrO4. It is found that the energy gap of Sr2IrO4 is rapidly decreased with a small amount of Zn doping. Consequently, the electrical conductivity is significantly enhanced. The present work could serve as the prerequisite stage in exploring the possible superconductivity of the Sr2IrO4 compound. [ABSTRACT FROM AUTHOR]

Abstract This study demonstrates the hydrogen (H) storage process on titanium (Ti) atom doped divacancy (DV) hexagonal boron nitride (h-BN) system using first-principles density functional theory (DFT). Two configurations were adopted for H storage on the h-BN system. In first approach, H 2 molecules were adsorbed on one side and in second approach H 2 molecules were adsorbed on both sides of the Ti-atom substituted DV h-BN system. The binding energies of each system for both of these adsorption approaches were calculated, and it was revealed that the system having H 2 molecules adsorbed on both sides of h-BN layer produce improved binding energy in comparison to single sided H 2 adsorption on Ti decorated h-BN layer. These findings suggest that storing H 2 molecules on double sides of Ti-atom substituted DV h-BN system is a preferred approach in comparison to single sided adsorption. The electronic and magnetic properties of H 2 adsorbed Ti atom substituted DV BN complexes were also calculated. Further, spin-polarized band structure analysis suggested that the H 2 adsorption along with Ti atom substitution at DV site converts insulating h-BN material to a narrow band semiconducting material. In addition, the difference in gap opening during positive and negative spin is substantial making it viable for spintronic applications. The obtained band gap values were in the range of 1–2.5 eV for different H 2 -adsorbed Ti atom substituted DV h-BN systems respectively. Also, the H 2 -molecule adsorption on Ti atom substituted DV h-BN system introduces finite magnetic moments ranging up to 2.00 μ B , thus producing a magnetic h-BN material by nature. The density of states (DOS) plots were generated to observe the origin of magnetism and orbital occupation. It is observed that the d orbitals of Ti atom mainly attribute to the magnetic behavior of DV h-BN system. The results of this study establish that Ti atom-doped DV h-BN system is geometrically stable and it can provide higher hydrogen storage capability. Highlights • Hydrogen adsorption on Ti decorated h-BN layer is investigated through DFT method. • Double sided H 2 molecules adsorption on h-BN layer is more stable approach than single sided adsorption. • H 2 molecule adsorption and Ti substitution makes h-BN a narrow band gap semiconductor. • Five different orbitals (d xy , d yz , d z 2, d xz and d x 2 -y 2) of Ti atom mainly induce magnetic moments in BLG system. • Double sided H 2 adsorption is thermodynamically stable process owing to their improved adsorption energies. [ABSTRACT FROM AUTHOR]

Highlights • Magnetic and electronic properties of Cd 1-x Zn x Cr 2 Se 4 have been studied experimentally and theoretically. • The difference in energy between the antiferromagnetic (AFM) and ferromagnetic (FM) states reveals the magnetic competition coexisting in this system. • All samples were found to keep 100% spin polarization and behave as half-metallics. Abstract We have studied the magnetism of crystalline Cd 1-x Zn x Cr 2 Se 4 spinels with (0.35 ≤ x ≤ 0.55) under magnetic field up to 15 T. The total magnetic moment, Curie temperature, lattice parameter and exchange integrals were found to decrease with Zn substitution. Ab -initio calculations carried out using full potential augmented plane wave (FP-LAPW) method were performed to study the magnetic, and electronic structure using generalized gradient approximation (GGA) and the modified Becke-Johnson (mBJ) to correct the gap's energy. The obtained results were in good agreement with the experimental ones. It is shown that there is a competition between ferromagnetic (FM) and antiferromagnetic (AFM) interactions: the super-exchange mechanism slightly increases the AFM contribution and keeps the FM the dominant mechanism in this range of substitution. From the density of states, we demonstrate that the system keeps the half-metallic state for the composition range 0.125 ≤ x ≤ 0.55 with 100% spin polarization. Our results highlight that it is possible to obtain a half-metallic semiconductor with tunable magnetic state which is promising for applications in spintronics. [ABSTRACT FROM AUTHOR]

Highlights • Effects of spins on structural, electronic and magnetic properties of Mg 1−x Fe x O and Mg 1−x Ni x O. • Electronic band structure, density of states and magnetic moment values are determined. • Magnetic character in majority and minority spins is treated. • Mg 1−x Ni x O exhibits a magnetic insulator character which is suitable in magneto-optical devices. • Mg 1−x Ni x O reveals ferromagnetic behavior thereby could be used in spintronic devices. Abstract Full potential linearized augmented plane wave (FP-LAPW) method based on the density functional theory (DFT) is used to investigate the structural, electronic and magnetic properties of Fe and Ni (3d transition metal) substituted Rock-salt wide band gap insulator M g 1 - x M x O (M = Fe, Ni). We have performed spin polarized calculations throughout this work with generalized gradient approximation (GGA) type exchange correlation functional. Additionally, the electronic structures and density of states are computed using modified Becke-Johnson (mBJ) potential based approximation with the inclusion of coulomb energy (U = 7 eV). Based on the Vegard's law and structural optimization, the lattice parameter and bulk modulus are found to be in good agreement with experimental values. Moreover, the analysis of electronic band structures reveals an insulating character for Ni substituted MgO while semiconducting and half-metallic character for Fe substituted case. It has been found that the p-d super-exchange interaction provides a ferromagnetic character due to the 3d transition metal impurities and oxygen atom. The observed p-d hybridization at the top of the valence band edge in this investigations could be useful for magneto-optic and spintronic applications. PACS: 61.66.Dk; 71.15.Mb; 71.15.Nc; 71.20.Nr; 71.22.+ i. [ABSTRACT FROM AUTHOR]

The electronic band structure and related band parameters such as, lattice parameters, energy band gaps, density of states and magnetic moment of Zn1−xMnxO ternary system in the hypothetical hexagonal wurtzite structure have been investigated. The calculations are performed using a full-potential linearized augmented plane wave method based on density functional theory in the generalized gradient approximation of Perdew-Burke-Ernzerhof. The evolution of the features of interest with increasing the Mn doping concentration from 0 to 1 in the ZnO structure has been examined and discussed. Our findings show that the behaviour of all studied band parameters with respect to the alloy composition x is consistent with those reported experimentally in the literature. The present study may be useful for spintronics applications. [ABSTRACT FROM AUTHOR]

The electronic structure, martensitic transformation and magnetic properties of Pd 2 MnGa Heusler alloy were studied by first-principles calculations. It is found that the stable structure of austenitic Pd 2 MnGa is the ferromagnetic L 2 1 structure, and a martensitic transformation is possible to occur with the distortion degree of 1.26. By the analysis of the electronic structure, some results of magnetic moment are consistent with previous theoretical calculations. [ABSTRACT FROM AUTHOR]

Abstract In this article, we have synthesized the Polypyrrole/Ba 0.6 Sr 0.4 Fe 12 O 19 (PBSF) composite via in-situ polymerization technique. The synthesized samples were further characterized for structural, electrical, magnetic and microwave absorbing characterizations. The X-ray diffraction patterns reveal the formation of pure hexagonal ferrite phase whereas the Fourier transform infrared spectrums and X-ray photoelectron spectroscopy confirms the formation of polypyrrole/BSF composite structure. The microwave absorbing and shielding properties were studied in the frequency range 8–18 GHz. Using X and Ku band. The magnetic properties were studied using VSM and the PBSF37 composite shows the highest magnetic moment 59.58 emu/gm rather than the other PBSF composites and pure BSF ferrite. The PBSF37 shows the maximum microwave absorption of 89% over the broadband frequency range 8–18 GHz. The maximum shielding effectiveness 37.49 dB at 15.2 GHz corresponding maximum microwave properties were also observed for the same sample. Graphical abstract Image 1 Highlights • Simple and cost effective In-situ chemical polymerization technique has been used for synthesis. • First time studied the microwave properties of divalent substituted hard ferrite, polymer composite. • Maximum microwave absorption, shielding effectiveness and magnetic moment obtained for 30:70% composition i.e. for PBSF37 sample. • The final composition can be used for the application of stealth technology as a coating for aircraft. [ABSTRACT FROM AUTHOR]

Abstract The magnetoelectric composites with the compositions of ferrites & ferroelectrics having the general chemical formula (x) Ni 0.8 Mg 0.2 Fe 2 O 4 + (1-x) BaZr 0.2 Ti 0.8 O 3 (in which x = 0.1, 0.2, 0.3) were synthesized by using double sintering ceramic technique. From XRD, the phase formation of ferrites with cubic structure and ferroelectrics with tetragonal perovskite structure was confirmed through the measurement of XRD. The two phase ME composites have larger saturation magnetization and dielectric constant; it is because of the effect of interfacial strain on BaZr 0.2 Ti 0.8 O 3 ferroelectric phase. Furthermore, the ME response 4.262 mVcm−1Oe−1 was observed for (30%) Ni 0.8 Mg 0.2 Fe 2 O 4 + (70%) BaZr 0.2 Ti 0.8 O 3 composites at 5.0 kOe applied DC magnetic field; it shows the success of magnetic control of the dielectric response via the mechanical coupling which can be exploited in the future applications of multiferroic composites. Highlights • Magnetoelectric composites synthesized using solid state reaction method. • Structural, electrical, magnetic & magnetoelectric properties were studied. • These materials gain more importance in modern technology from last few decades. • Observation of giant ME output promise the potential applications in many devices. [ABSTRACT FROM AUTHOR]

Structural, electronic, intrinsic magnetic, anisotropic elastic properties, sound velocities and Debye temperature of Fe1−xMnx B (x = 0, 0.25, 0.5, 0.75, 1) transition metal monoborides have been studied by first-principles calculations within the method of virtual crystal approximation (VCA) based on density-functional theory (DFT) through generalized gradient approximation (GGA). The average magnetic moment per cell increased with increasing of Mn content, which could be associated with the relationship between the composition and magnetic properties. The observed magnetic behavior of Fe1−xMnx B compounds can be explained by Stoner model. Lattice parameters and Debye temperature agree well with the experimental values. Furthermore, we have plotted three-dimensional (3D) surfaces and planar contours of the directional dependent Young and bulk moduli of the compounds on several crystallographic planes, to reveal their elastic anisotropy versus Mn content (x) in Fe1−xMnx B. [ABSTRACT FROM AUTHOR]

Abstract By means of first-principles calculations together with torque method, we investigated the magnetic moment and magnetocrystalline anisotropy energy (MAE) for monolayers of organometallic framework TM 3 C 12 S 12 with transition metal element TM (ndm with n = 3–5 and m = 4–8). According to square planar ligand field with weak interaction, the magnetic moment follows -|m-5|+3 for 3d transition metals. Interestingly, we find that Re 3 C 12 S 12 has huge MAE about 13.54 meV with an easy axis perpendicular to TM 3 C 12 S 12 plane. Moreover, our calculations pointed out that the MAE of Re 3 C 12 S 12 can further enhance to 20.97 meV with tensile strain 5%. Our results provide a reliable guideline to manipulate the MAE of the magnetic materials in magnetic storage devices. Highlights • A novel ordering structure 2D material TM 3 C 12 S 12 with an outstanding MAE. • The magnetic moment can be explained by the ligand field theory. • Re 3 C 12 S 12 has huge MAE about 13.54 meV. • The MAE of Re 3 C 12 S 12 can further enhance to 20.97 meV with tensile strain 5%. [ABSTRACT FROM AUTHOR]

Investigations of the electronic structure, elastic, magnetic, and optical properties of Fe2MnZ (Z = Si, Ge, and Sn) full Heusler alloys show mechanical stability with cubic symmetry in all three alloys. They are elastically anisotropic and Fe2MnSi is ductile whereas Fe2MnGe and Fe2MnSn are brittle in nature. The value of total magnetic moment is 3 μ B for Fe2MnSi and Fe2MnGe at their equilibrium lattice constants and follows the Slater–Pauling curve. Fe2MnSn possess the largest magnetic moment among the three with a value of 5.73 μ B at equilibrium lattice constant. Fe2MnSi shows half-metallic nature with 100% spin polarization for a wide range of lattice parameters and is useful for spintronics devices. Good optical properties over wide photon energies point to the possible use of these alloys as radiation shielding materials, optical filters, and photo-electronic devices. [ABSTRACT FROM AUTHOR]

In recent times, spin gapless semiconductors (SGS) have attracted much attention as a promising candidate for spintronics and thermoelectric applications due to their high carrier concentration and good thermoelectric figure of merit. In this paper, we have carried out a systematic theoretical investigation of the structural, elastic, thermal, electronic, magnetic, thermoelectric, lattice dynamical and thermodynamical properties of Zr2MnIn using density functional theory (DFT) based first principle calculations. The band structure calculation shows indirect band gap in a spin down channel and zero band gap in a spin up channel of valence and conduction bands confirming the spin gapless semiconducting nature of Zr2MnIn. The structural and dynamical stability of the antiferromagnetic phase of Zr2MnIn has also been investigated. Magnetization in Zr2MnIn originates due to the d state electrons of Zr atoms, which follows the Slater Pauling rule: Mt = Zt − 18. Phonon dispersion curves exhibit real frequency of phonon modes throughout the Brillouin zone, which confirms the dynamical stability of the antiferromagnetic phase of Zr2MnIn. Thermodynamical properties including specific heat and Debye temperature have been calculated using phonon density of states. A higher value of the thermoelectric figure of merit 1.25, predicts that this alloy as good thermoelectric properties with better output efficiency. [ABSTRACT FROM AUTHOR]

Abstract We present here the magneto thermal properties, damping behavior and effect of Cerium doping on ferromagnetic insulator Yttrium Iron Garnet (YIG), synthesized via solid state method and Spark Plasma Sintering. The thermal conductivity was measured using Laser Flash technique in the temperature range of 300–1000° K. A decrease in thermal conductivity was observed up to the Curie temperature of YIG, beyond which it showed a constant behavior. On Ce doping of YIG, 15% enhancement of thermal conductivity was achieved, besides leading to an increase of magnetic moment at all temperatures. This gain is attributed to the increase of grain size and replacement of diamagnetic Y3+ ions in YIG by paramagnetic Ce3+ ions in Ce doped YIG. The spark plasma sintered YIG showed a decrease in particle size and grain size resulting in decrease of both thermal conductivity and saturation magnetization. The damping parameters obtained from ferromagnetic resonance measurement revealed a very low magnetic damping even on Ce doping. The work provides effective information regarding the enhancement of spin dynamic properties of YIG suitable for spin-caloritronic applications. [ABSTRACT FROM AUTHOR]

The melt-spun SmFe12Bx (x = 0, 0.50, 0.75, 1.00, 1.25 and 1.50) ribbons were prepared at 40 m·s−1, and their structure and magnetic properties were studied by powder X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and transmission electron microscopy (TEM). XRD results indicate that SmFe12Bx alloys with 0.50 ≤ x ≤ 1.00 are composed of single-phase TbCu7-type structure. Moreover, it is found that the boron addition can inhibit the emergence of soft magnetic phase α-Fe and result in the increase in the axial ratio c/a. After annealing at 650 °C for 0.5 h, the metastable phase TbCu7 initially decomposes into the stable phase Sm2Fe14B (Nd2Fe14B-type) and α-Fe. The value of magnetic moment per Fe atom increases slightly from 1.75μB for boron-free sample to 1.80μB for the x = 0.75 sample and then decreases again. In addition, the best magnetic properties of maximum energy product [(BH)max] of 14.56 kJ·m−3, coercivity (Hcj) of 172.6 kA·m−1 and remanence (Br) of 0.45T are obtained for the SmFe12B1.00 alloy. Based on transmission electron microscopy (TEM) results, the average size of grains is around 197 nm for B-free sample and decreases to 95 nm for x = 1.00 sample, indicating that the addition of boron can refine grains. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The electronic and magnetic properties of the VLi 8 on graphene were studied by DFT. • The VLi 8 on graphene can maintain its structure regardless of the type of adsorption. • The VLi 8 on graphene has an enhanced magnetism compared to VLi 8 superatom. • The VLi 8 superatom on the graphene surface exhibit a robust ferromagnetic coupling. Abstract We present a density functional theory (DFT) study of the structural, electronic and magnetic properties of the superatom VLi 8 supported on graphene surface. The four typical configurations of VLi 8 superatom in contact with graphene surfaces are a square contact configuration (Squ-contact), a triangle contact configuration (Tri-contact), a linear contact configuration (Lin-contact) and a vertex contact configuration (Ver-contact), respectively. The results show that the VLi 8 superatom adsorbed on the surface of graphene maintains its structural stability regardless of the type of adsorption and has an enhanced magnetism (approximate 6 μ B /cell) compared to free VLi 8 superatom (5 μ B). The further calculation also shows that the VLi 8 superatom on graphene exhibit a robust ferromagnetic coupling. Our research on superatomic assembly provides a new way to develop new magnetic film nanomaterials. [ABSTRACT FROM AUTHOR]

Abstract We have investigated the spin and orbital moments of Ir-based double perovskites with 5 d n (n = 3, 4, 5) states by local spin-density approximation with spin-orbital coupling and Hubbard correlation (LSDA+SOC+U). Our calculations reveal that the ratio of orbital to spin momentum L z / S z approaches to certain values for the double perovskites with different 5d n (n = 3, 4, 5) shell fillings. Based on d orbits, a spin-orbital coupling model with exchange splitting is proposed and it can well describe the ratio of angular momentums for the compounds. Our model calculations reveal that L z / S z is determined by the exchange splitting, spin-orbital coupling as well as the state of shell filling. Our model is well corroborated by the experiments and density-functional calculations. Highlights • Spin and angular momentums of the series of Ir-based double perovskites have been studied by LDA+U+SOC method. • Our calculations reveal that the L z / S z values approach to certain values for the 5 d n cations of Ir. • A d -orbit-based model was proposed to explain the results of density-functional calculations and the experiments. [ABSTRACT FROM AUTHOR]

The magnetic field of different geometry of the permanent magnet is analytically calculated by using basic principles of the magnetism in very easier approach. Concept of origin shifting and geometrical shape transformation are used to formulate the formula for cuboidal, cubical and cylindrical permanent magnets. This concept can be used for the analysis of magnetic field distribution in space around for permanent magnet as well as electromagnet in a very easier approach. Handy and simplified software is made to calculate the magnetic field due to permanent magnet and electromagnet at any desired position on space. Magnetic field visualization is also done in both magnitude and direction by using MATLAB. [ABSTRACT FROM AUTHOR]

We investigate the structural, electronic and magnetic properties of the full Heusler compounds Mn_2YSn (Y = Mo, Nb, Zr) by first- principles density functional theory using the generalized gradient approximation. It is found that the calculated lattice constants are in good agreement with the theoretical values. We observe that the Cu_2MnAl-type structure is more stable than the Hg_2CuTi type. The calculated total magnetic moments of Mn_2NbSn and Mn_2ZrSn are 1 μB and 2 μB at the equilibrium lattice constant of 6.18 Å and 6.31 Å, respectively, for the Cu_2MnAl-type structure. Mn_2MoSn have a metallic character in both Hg_2CuTi and Cu_2MnAl type structures. The total spin magnetic moment obeys the Slater-Pauling rule. Half-metal exhibits 100% spin polarization at the Fermi level. Thus, these alloys are promising magnetic candidates in spintronic devices.

• The effect of strain on nickel-based materials with doping elements are studied. • Cu atoms enhance the magnetic moment while Nb atoms play an inhibitory role. • The atomic magnetic moment of pure nickel increases monotonically with strains. • Doping elements' effect on magnetic moment is related to nickel atoms' distances. Based on the magneto-mechanical coupling effect, magnetic non-destructive testing technology is widely used to test stress and defect in ferromagnetic materials. To analyze the effect of strain/stress on the atomic magnetism of Ni-based materials strain-induced changes of magnetic properties of FCC-Ni 2 × 2 × 2 supercell and its doped systems with Cu and Nb atoms are studied by the first principal density functional theory. Firstly, addition of Cu or Nb promote the expansion of nickel lattice, and Nb makes this effect more significant. Cu atoms enhance the magnetic moment of Ni atoms, while Nb atoms play an inhibitory role. Secondly, for uniaxial strain, the magnetic moments of atoms in the doping-free systems show a nearly monotonic increasing trend from compression to tension, while the doped systems show a trend of first increases and then decreases. Furthermore, for shear loading, the atomic magnetic moment decreases with increases of the shear strain. Further investigation shows that Ni atoms at different distances exhibit completely different magnetic behavior due to the influence of loadings and doping atoms. This study would be an important supplement to the physical mechanism of multi-field coupling in magnetic non-destructive testing. [ABSTRACT FROM AUTHOR]

A detailed study of magnetic behaviour of double perovskites was carried out by developing La 2 Co 1- x Fe x MnO 6 ; (x = 0.0, 0.2, 0.5, 0.8 and 1.0) via sol–gel technique. All samples showed single magnetic transition except pure LCMO (x = 0.0) and LCFMO2 (x = 0.5). Temperature dependent inverse magnetic susceptibility (χ-1) was fitted in accordance with Curie-Weiss law. μ eff (effective magnetic moment) was determined for all the developed samples. Pure LCMO showed a downward divergence from Curie-Weiss law below 230 K but above transition temperature which indicates the characteristics of Griffiths phase. Saturation magnetization (M s) increased initially and then decreased, whereas coercive field (H c) was found to be monotonous decreased with increase in Fe content. LCFMO1 (x = 0.2) was noticed to have maximum M s (38.87 emu/g) which indicated that the magnetic properties of pure LCMO were improved with Fe substitution, but for lower substitution only. Magnetization vs. field (M−H) curves were not well saturated even at a magnetic field of 60 kOe, therefore, values of M s for all the samples were estimated using law of approach to saturation. With increase in Fe content, an increased anti-site disorder among Mn and Co strengthened antiferromagnetic (AFM) super exchange interactions and weakened ferromagnetism (FM). Therefore, substitution of Fe on Co-site was responsible for systematic decrease in saturation magnetization when × exceeded 0.2. [ABSTRACT FROM AUTHOR]

• The Si-doped Fe 2 P alloys show the high magnetic moment of 3 uB per formula unit under the different strains. • The 4.2% Si-doped Fe 2 P alloy under the different strains shows the robust magnetic property. • The magnetic moments of the Si-doped Fe 2 P alloys are contributed from Fe-3d orbitals. • The transition from the ferromagnetic metal to the ferromagnetic half-metal can be achieved for the Si-doped Fe 2 P alloys by strain engineering. Si-doped Fe 2 P alloys have attracted attentions due to the potential magnetocaloric applications. To explore the magnetic property of the 0%, 4.2% and 8.3% Si-doped Fe 2 P alloys with the strain from −2% to 5%, their electronic structures are studied systemically by using the high throughput first-principle calculations. The calculated results show that, under the different strains, the ground state structures of all doped alloys have the magnetic moment about 3 uB per formula unit, and their magnetic moments are contributed from Fe-3 d orbitals. Moreover, the transition from the ferromagnetic half-metal to metal properties can be achieved for the Fe 2 P alloy via the strain engineering, these results suggest that the Si-doped alloys can be applied to the magnetic devices. [ABSTRACT FROM AUTHOR]

• Role of magnetic moment in catalytic activity. • Effect on the magnetic moment on the d-band center. • Effect of bimetallic on the stability of single-atom catalyst on adjacent position. • Evaluating of z-directed orbital for catalytic activity. • Tuning of electronic structure for oxidative and reductive species. Numerous articles on M-N-C-based materials have been extensively studied for their catalytic activity in various reaction perspectives, such as CO oxidation, CO 2 reduction, oxygen reduction, and oxygen/hydrogen evaluation. However, the understanding of the involvement of d-orbitals of transition metal atoms and the tunability of their electronic structure for different catalytic species is under observation. Herein we have suggested bimetallic iron-doped nitrogen-based graphene FeN 4 -MN 4 /Gr (M= Co, Ni, Cu, Zn) and single-atom iron-doped nitrogen-based graphene for comparative study. The effect of bimetallic atoms on iron on the adjacent position was studied by Bader charge, adsorption energy for different species, and the strengthening of iron nitrogen codoped graphene Fe-N 4 /Gr. Moving from Co to Zn, the number of outermost electrons is increasing, creating steric hindrances effect and torsional strain, affecting Bader charge and formation energy and changing the bond length between nitrogen and iron. Similarly, steric hindrance also has a prominent effect on the d-orbital, as moving from Co to Zn, the availability of finding of d-orbital on z-direction are increasing which is confirmed by adsorption energy of different species like Co, O 2 , and H+ + e−. Our finding reveals that not only d-orbitals along the z-direction can play a vital role in catalytic activity, but the d-band center and magnetic moment also have a projecting role in boosting catalytic activity. [Display omitted] [ABSTRACT FROM AUTHOR]

The adjustable magnetic moments of REGe 6 − clusters increase monotonically. [Display omitted] • The dopant atoms are basically located at the top (or side) of pentagonal bipyramid. • The results of the theoretical study provide theoretical guidance for future experiments in anion photoelectron spectroscopy. • The adjustable magnetic moments of REGe 6 − (RE = Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu) clusters increase monotonically from 0 to 8µ B. • Most regions of the REGe 6 − clusters exhibit strong aromaticity. The geometries, electronic, and magnetic properties in a series of rare-earth (RE) metal atoms (Sc, Y, La, Ce, Pr, Nd, Pm, Sm, and Eu) doped Ge clusters, REGe 6 −, are investigated using density functional theory calculations and the results are compared with experimental literature data. It was found that all REGe 6 − clusters have similar pentagonal bipyramid structures, where the RE atom is located at the top (or side) of the pentagonal bipyramid. Natural population analysis reveals that the electrons always transfer from the RE atom to parent germanium atoms. The spin density and the density of states diagrams visually showed that the magnetic moments increase monotonically from Sc to Eu, which mainly derive from the contribution of the RE atoms. Isochemical shielding surfaces analyses indicate that the most regions of the REGe 6 − clusters (i.e., the pentagonal and the tetragonal ring in REGe 6 −) exhibit strong aromaticity compared with the benzene ring. [ABSTRACT FROM AUTHOR]

Magnetic and photoluminescence properties of pure BaTiO 3 and doped BaTiO 3 : Mn compounds were studied experimentally and theoretically. The broad band of high intensity observed in the photoluminescence spectrum covers the visible region (400–650 nm). This maximum coincides with the emission lines due to the 1 T4--- 6 A1 interatomic optical transition of the Mn ion and dramatically increases the photoluminescence intensity over a large region due to the absorbed photon energy. Results from the Color Calculator CRI show that this combination is suitable for display (and lighting) and white light emitting diode applications. Optical and magnetic properties of pure and doped BaTiO 3 :Mn compounds studied based on a larger supercell size of 180 atoms from first principle. With the replacement of Mn atoms, the peak of the optical spectrum for the imaginary part of the dielectric function shifts towards lower energies due to the reduction of the band gap. The ferromagnetic phase is stable for the structure regardless of the concentration of Mn atoms. • The aims of this article is to provide useful information on photoluminescence, excitation spectra and DFT calculation of BaTiO3 and BaTiO3:Mn. • A systematic study of CIE chromaticity coordinates showed that this compound is a promising material for white light-emitting diodes. • DFT calculation shows that regardless of manganese concentration ferromagnetic phase is stable. [ABSTRACT FROM AUTHOR]

Obtaining a new optimal law of controlling onboard magnetic coils that would provide reduction of the angular momentum of nanosatellites and microsatellites to a predetermined small value and subsequently maintaining it is discussed in the paper. The study shows that the use of a new time-optimal control law contributes to a significant increase in the high speed performance of the magnetic attitude control system in the tasks of reducing angular momentum of satellites to small values. The problem of satellite angular rate damping in accordance with a reference model a system of three independent linear homogeneous equations is discussed as well. Some numerical results of the application of these laws to the problem of reduction of satellite angular momentum and angular velocity are presented. Advantages and drawbacks of the new time-optimal laws of control of angular momentum of nanosatellites and microsatellites are specified.

Band structure of solid solutions InxGa1-xN with sphalerite structure and with considerable percentage of indium (x = 0,25; 0,5; 0,6; 0,7; 0,75; 0,9; 0,95; 0,97; 0,99; 1,0 ) is calculated using the density-functional theory (DFT) and the cluster version of the local coherent potential method within the frame of the multiple scattering theory. The electron structure of the ternary solutions of InxGa1-xN in sphalerite crystallographic modification is compared; the interpretation of their features is given. The concentration dependence on the energy gap for the entire variation range of the indium content in the solution is obtained. The spin polarization effect of the states of In, Ga, and N for the alloys with the considerable percentage of In, as well as the transition of the ternary solutions of In0.75Ga0.25N into the of magnetic semiconductor state is found out. The magnetic moments of In, Ga, and N atoms, and the saturation magnetization in InxGa1-xN semiconductor system are determined.

First-principle calculations were performed in order to investigate the structural, electronic and magnetic properties of 1x1 MnO/ZnO superlattice in the wurtzite-type structure. The full-potential linearized augmented-plane-wave (FP-LAPW) method was used, as implemented in the WIEN2k computational code. Exchange and correlation effects are treated using the generalized gradient approximation (GGA) of PerdewBurke-Ernzerhof (PBE). The analyze of the structural properties show that the value of the bulk moduli is high, therefore is quite rigid and this feature makes them good candidates for possible application in devices that have to operate at high temperatures, under high power, and in hard coatings. The electronic density studies show that the MnO/ZnO superlattice have a half-metallic behavior with a magnetic spin polarization of 100% and a magnetic moment of 5 µβ/atom-Mn in the ground state. The ferromagnetic state comes from the hybridization of the Mn-3d and O-2p states that cross the Fermi level. This superlattice is a good candidate for spintronic applications.