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Half metallic ferromagnets play a pivotal role in spintronic applications. Our study focuses on theoretically predicted half metallic ferromagnetic compounds, determined through density functional theory calculations utilizing a first principles approach. The calculations involved the use of Perdew-Burke-Ernzerhof (GGA) and GGA + U exchange correlation energies. Structural analysis revealed the ferromagnetic nature, while electronic properties confirmed the half metallic behavior of these compounds-specifically, Cu 2 CoS and Zn 2 CoS. Our findings suggest that within a certain lattice parameter range, both compounds exhibit ferromagnetic behavior. However, beyond this range, Cu 2 CoS and Zn 2 CoS do not demonstrate ferromagnetism. Furthermore, our interest lies in examining their thermoelectric behavior using semi-classical Boltzmann transport theory. These results offer valuable insights for leveraging these materials in spintronics applications. • The ground state energy of ferromagnetic state (FM) is lower than non-magnetic (NM) and antiferromagnetic (AFM) state for both Cu 2 CoS and Zn 2 CoS compound. • The semiconducting and metallic nature is observed for both Cu 2 CoS and Zn 2 CoS compound. • Cu 2 CoS has E g of 1.05 eV and Zn 2 CoS has E g of 0.392 eV in spin up case. • Magnetic moments were calculated to be 3 μ B and 1.02 μ B. [ABSTRACT FROM AUTHOR]

The efficiency of a magnetic system of kinetic moment dumping in solving the problem of stabilizing Aist-2D spacecraft without using information on angular velocity is investigated. We defined the conditions under which the magnetic moment produced by electromagnets constitutes a useful control mechanical moment. Boundary conditions for preventing emergence of the parasitic moment are also defined. The paper presents the solution of the problem of forming the vector of the kinetic moment of the system “spacecraft + control moment gyro” according to the information on the vector of geomagnetic induction of the Earth. We defined the dependence of the time taken by the algorithm of angular speed reduction on the value and direction of the projections of the vector of spacecraft angular speeds at the time of algorithm actuation. The results obtained in the course of mathematical modeling and natural experiment on the spacecraft, the process of dumping angular speeds in providing the solution of the problem of attitude determination with the use of star sensors are compared.

It is interesting to understand the effect of defects in 2D materials because vacancy defects in 2D materials have novel electronic and magnetic properties. In this work, we studied electronic and magnetic properties of 1S vacancy defect (1Sv-MoS2), 2S vacancy defects (2Sv-MoS2), 1Mo vacancy defect (Mov-MoS2), and (1Mo & 1S) vacancy defects ((Mo-S)v-MoS2) in 2D MoS2 material by first-principles calculations within spin-polarized density functional theory (DFT) method. To understand the electronic properties of materials, we have analyzed band structures and DOS calculations and found that 1Sv-MoS2 & 2Sv-MoS2 materials have semiconducting nature. This is because, 1Sv-MoS2 & 2Sv-MoS2 materials open a small energy band gap of values 0.68 eV & 0.54 eV respectively in band structures. But, in Mov-MoS2 & (Mo-S)v-MoS2 materials, energy bands around the Fermi level mix with the orbital’s of Mo and S atoms. As a result, bands are split and raised around and above the Fermi energy level. Therefore, Mov-MoS2 & (Mo-S)v-MoS2 materials have metallic nature. We found that MoS2, 1Sv-MoS2 & 2Sv-MoS2 materials have non-magnetic properties, and Mov-MoS2 & (Mo-S)v-MoS2 materials have magnetic properties because magnetic moment of MoS2, 1Sv-MoS2 & 2Sv-MoS2 materials have 0.00 µB/cell value and Mov-MoS2 & (Mo-S)v-MoS2 materials have 2.72 µB/cell & 0.99 µB/cell respectively. Therefore, non-magnetic MoS2 changes to magnetic Mov-MoS2 & (Mo-S)v-MoS2 materials due to Mo and (1Mo & 1S) vacancy defects. The magnetic moment obtained in Mov-MoS2 & (Mo-S)v-MoS2 materials due to the distribution of up and down spins in 4p, 4d & 5s orbitals of Mo atoms and 3s & 3p orbitals of S atoms in structures. The significant values of the magnetic moment are given by distributed spins in 4d orbital of Mo atoms and 3p orbital of S atoms. BIBECHANA 18 (2) (2021) 68-79

Rare earth (RE)-based MgCu 2 -type intermetallic compounds are studied by first-principles calculations to search their spintronic applications and thermodynamic stability. We found in our observations that both EuPt 2 and GdPt 2 have half-metallic properties. The band gap arises in spin-down channel which is found to be enhanced when we move from EuPt 2 (0.91 eV) to GdPt 2 (1.04 eV). From magnetic properties we got to know that the magnetic moments of RE and Pt are opposite in direction and total magnetic moment is found to be 7.01 μ B and 4.1 μ B for EuPt 2 and GdPt 2 respectively. Presence of 5 d 1 electron in Gd valance shell is the reason for this difference in magnetic moments. No negative frequency has been observed in the phonon dispersion curve of both systems indicating the dynamic stability of MgCu 2 -type structure. Several thermodynamical potentials are also explored in the present study using quasiharmonic approximation. The half-metallicity of dynamically stable REPt 2 systems is appropriate for spintronic applications. [ABSTRACT FROM AUTHOR]

The paper investigated the Zigzag GaN nanoribbons (ZGaNNR) using the density functional theory(DFT) and non equilibrium Green's function(NEGF) framework. We have calculated the structural, electronic and transport properties of various Fe-ZGaNNR configurations. Based on the binding energy( E B ) calculations, Fe-doped@Ga_edge ZGaNNR(-6.51eV) is observed to be most structurally stable among different configurations. Our findings show the substitutional Fe passivation provides a stable bonding as compared to pristine configuration. The magnetic moment of different configurations depends upon the position of Fe atom. The discontinuity is observed in degenerative states of spin modes and same is follows by their respective density of states(DOS) and projected density of states(PDOS). Fe-termination@N_edge ZGaNNR is found to be a strong candidate for magnetic stabilization. High metallicity is observed in Fe-termination@both_the_edges ZGaNNR configuration. Further same is verified through current-voltage characteristics as current follow the pure linear behaviour. The practical application of the work on ZGaNNR can serve as a potential candidate for future low bias nanoscale spitronic devices and low power high speed interconnect applications. [ABSTRACT FROM AUTHOR]

The magnetically assembled chain-like structures of magnetic nanoparticles attract great attention due to their unique properties. In this paper, we studied the influences of essential magnetic controlling parameters on the chain-like structures of magnetic nanoparticles with diameter d = 360 nm using a 3D Monte Carlo simulation. The magnetic moment and volume fraction of magnetic nanoparticles were found to play crucial roles in the arrangement of the nanoparticles. The simulation results were in agreement with experimental evidence, summarized as follows: In the limit of low magnetic moment m < 3.7×10−16 A∙m2, magnetic nanoparticles did not linearly arrange along the direction of the magnetic field but formed aggregates. At magnetic moment m > 1.5×10−15 A∙m2 and volume fraction φ<0.02%, the formation effect of nanochains consisting of individual particles was first enhanced and then remained almost unchanged with increasing magnetic moment. For magnetic moment m>7.3×10−15 A∙m2 and volume fraction φ>1%, nanochains gradually coarsened into the nanobundles with increasing volume fraction. The results can provide a theoretical basis to construct and regulate other assembled structures consisting of building blocks. [ABSTRACT FROM AUTHOR]

Dielectric and magnetic properties of the Nd2– xCexCuO4 + δ bulk single crystal with x = 0.1 are studied in this work. The anisotropy of the field and temperature dependences of the specific magnetization is found. The value of specific magnetization measured in the magnetic field applied in parallel to CuO2 planes is higher than that measured in the magnetic field applied perpendicular to the planes; this is related to the additional contribution of magnetic moments of neodymium ions. In this case, at temperatures T < 100 K, when the magnetic field H is perpendicular to CuO2 planes, an area of antiferromagnetic coupling of ions exists within the CuO2 planes, which is not observed in the case of the parallel orientation of the magnetic field with respect to the CuO2 planes. Microwave studies show the existence of strong permittivity dispersion, which indicates the presence of natural resonance frequency, whose value is beyond the frequency range of performed measurements. [ABSTRACT FROM AUTHOR]

Taiji-1's in-orbit magnetic property is significant for the improvement of the satellite's attitude-control performance and the acceleration noise model of gravitational reference sensor. Test data of satellite drifts have been used to construct the model including interaction among the magnetic field; remnant magnetic moment and induced magnetic moment so as to estimate the satellite's magnetic property. Using the global optimization method, the remnant magnetic moment of Taiji-1 is estimated to be (-1.42 -0.19 -0.06) Am2. [ABSTRACT FROM AUTHOR]

Atomic-scale fabrication is an outstanding challenge and overarching goal for the nanoscience community. The practical implementation of moving and fixing atoms to a structure is non-trivial considering that one must spatially address the positioning of single atoms, provide a stabilizing scaffold to hold structures in place, and understand the details of their chemical bonding. Free-standing graphene offers a simplified platform for the development of atomic-scale fabrication and the focused electron beam in a scanning transmission electron microscope can be used to locally induce defects and sculpt the graphene. In this scenario, the graphene forms the stabilizing scaffold and the experimental question is whether a range of dopant atoms can be attached and incorporated into the lattice using a single technique and, from a theoretical perspective, we would like to know which dopants will create technologically interesting properties. Here, we demonstrate that the electron beam can be used to selectively and precisely insert a variety of transition metal atoms into graphene with highly localized control over the doping locations. We use first-principles density functional theory calculations with direct observation of the created structures to reveal the energetics of incorporating metal atoms into graphene and their magnetic, electronic, and quantum topological properties. • Electron beam manipulation used to insert a broad range of dopants into graphene. • Scanning transmission electron microscope allows high spatial control. • Density functional theory applied to a large block of the periodic table. • Electronic band gaps, magnetic moments, and non-trivial band topology are examined. [ABSTRACT FROM AUTHOR]

Structural evolution, magnetic moment, and thermochemical and spectral properties of NdSin0/− (n = 8–20) nanoclusters were studied. Optimized structures for NdSin demonstrated that the configuration with quintet ground state prefers Nd-substituted for a Si of the most stable Sin + 1 (n = 8–11) structure to Nd-linked configuration with Si9 tricapped trigonal prism subcluster (n = 12–19). Finally, the configuration prefers to Nd-encapsulated into Si cage framework (n = 20). For anion, the evolution at the quartet state prefers Nd-linked structure for n = 8–19 (excluded 9), and prefers Nd-encapsulated structure of n = 20. The spectral information including electron affinity, vertical detachment energy, and simulated photoelectron spectroscopy were also observed. The 4f electrons of Nd atom in NdSin with n = 8–10 hardly participate in bonding, but take part in remaining neutral clusters and all anionic NdSin− clusters. The calculations of average bond energy, HOMO-LUMO gap, and chemical bonding analyses reveal that NdSi20− possesses perfect thermodynamic and ideal chemical stability, making it as the most appropriate constitutional units for novel multi-functional semiconductors. [ABSTRACT FROM AUTHOR]

A deep insight into the electronic, structural, and magnetic properties of single-phase polycrystalline La2Ni1-xFexMnO6 double perovskites has been presented. X-ray photoelectron spectroscopy revealed that the Fe substitution resulted in a mixed-valence state for Ni and Mn in all samples. Rietveld analysis of the powder X-ray diffraction data suggested that all samples exhibited the orthorhombic structure with the Pbnm space group. Raman spectroscopy measurements indicated an increase in disorder of the system with Fe doping. The mixed-valence states and the accompanied disorder enhanced the competing magnetic exchange interactions in the samples resulting in a reduction of the ferromagnetic phase transition temperatures and saturation magnetic moments of the system. [ABSTRACT FROM AUTHOR]

First principles calculations have been accomplished for structural, electronic, magnetic and mechanical properties of half Heusler (HH) LiYZ (Y = Ru , Rh and Z = As , Se, Te, Sb) alloys using the density functional theory (DFT) within full potential-linearized augmented plane wave (FP-LAPW) method. To calculate the physical properties, Perdew–Burke–Ernzerhof (PBE) potential and generalized gradient approximation (GGA) are employed. The calculations are accomplished for three phases to obtain the most stable phase. The results of these calculations revealed that Type-III is the most stable of LiRhSe and LiRhSb, Type-I of LiRhAs, LiRhTe, LiRuAs, LiRuSb, LiRuSe and LiRuTe alloys. The structural optimization is obtained by plotting the graphs between minimum volume and the lowest energy of all considered alloys. The results of electronic properties including density of states (DOS) and band structures are also presented. The obtained total magnetic moment (MM) is negative for LiRhSb, LiRuSb, LiRhTe, LiRuTe, while it is positive for LiRhSe, LiRuSe, LiRhAs, LiRuAs Heusler alloys (HAs). To determine the mechanical stability, several parameters such as Poisson's ratio, Pugh's ratio, Lame's coefficient, anisotropy factor, Kleinman parameter, Young's modulus, Bulk modulus and Cauchy pressure are calculated and discussed in detail. [ABSTRACT FROM AUTHOR]

The ground‐state structures of europium‐doped Si nanocluster and their anions EuSin0/− (n = 11‐18) are verified by using the ABCluster unbiased global search technique married with density functional theory methods and matching of simulated and experimental photoelectron spectroscopy. The results revealed that structural growth pattern for neutral and anionic nanoclusters is from Eu‐substitutional to Eu‐linked structure starting from n = 13 and 12, respectively. The natural population analysis showed that the 4f electrons of Eu atom in EuSin0/− (n = 11‐18) hardly participate in bonding, resulting the total magnetic moments are 7 and 8 μB, respectively. The highest occupied molecular orbital‐lowest unoccupied molecular orbital gap and average bond energies of EuSin0/− (n = 11‐18) have also been calculated respectively to examine their thermodynamic and chemical stability. The result showed that EuSi15 nanocluster possesses good thermodynamic and chemical stability, which may make it as the most suitable building blocks for novel functional nanomaterials. [ABSTRACT FROM AUTHOR]

Summary: The ABC2 type ternary semiconductors have attracted much attention owing to their increasing fundamental and technological interest in optoelectronic, thermoelectric and nuclear detector applications. In this paper, using first‐principles methods, we first time reported on structural, optoelectronic, and thermophysical properties of two newly designed ABC2 type ternary semiconductor pnictides namely, K3Cu3P2 and K3Ni3P2. For the comparative analysis of the properties derived from density‐functional‐theory, we employed the most accurate full‐potential linearized augmented plane wave method. To count for electronic correlation and exchange interactions in compounds K3Cu3P2 and K3Ni3P2, we employed modified‐Becke‐Johnson potential and generalized‐gradient‐approximation (GGA) subjected to Hubbard potential U in the form of GGA + U method, respectively. Both the compounds are found to be stable mechanically and thermodynamically, and hence could be synthesized. From the calculated electronic band structures we predict direct band gap semiconducting nature of the compounds with band gap values of order 1.7 eV (spin up)and 1.82 eV (spin down)for K3Ni3P2 and 1.8 eV for K3Cu3P2. The density of states revealed that Ni‐3d and Cu‐3d states contribute mainly in the valence band of the compounds, having moderate spin symmetry in up and down spin polarized states. The calculated optical band gap for K3Ni3P2 is 1.9 eV (spin up) and 1.88 eV (spin down); while for K3Cu3P2 it is 1.8 eV. The optical spectra also showed that the main peak occurred due to hybridization of Ni/Cu‐d states. The optical dispersive spectra exhibit that both materials are efficient absorbers of photons in the UV region. On the other hand, the value of reflectivity is low in IR to visible region, while strong reflectivity is observed in UV part of the spectrum. To investigate the magnetic nature, the computed cell magnetic moment for K3Ni3P2 is 3.0 μB. As such, these materials are suitable in thermophysical and optoelectronic devise applications. [ABSTRACT FROM AUTHOR]

We investigate the structural, electronic and magnetic properties of the full Heusler compounds Mn2YSn (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 Cu2MnAl-type structure is more stable than the Hg2CuTi type. The calculated total magnetic moments of Mn2NbSn and Mn2ZrSn are 1/n; and 2/n; at the equilibrium lattice constant of 6.18 and 6.31, respectively, for the Cu2MnAl-type structure. Mn2MoSn have a metallic character in both Hg2CuTi and Cu2MnAl type structures. Thetotal spin magneticmoment 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. [ABSTRACT FROM AUTHOR]

The spin-polarized electronic band structures, density of states and optical and magnetic properties of dilute magnetic semiconductors (DMSs) Cd1−xMnxS with 6.25%, 12.5% and 25% concentrations of Mn have been studied by using ab initio calculations. The electronic band structures show half metallic ferromagnetic (HMF) behaviour with direct band gap at Γ symmetry point. The calculated values of band gaps are 0.8 eV, 0.99 eV, 1.3 eV and 1.5 eV for CdS, Cd0.9375Mn0.0625S, Cd0.875Mn0.1250S and Cd0.75Mn0.25S, respectively. The energy gap of CdS was found to increase by doping with transition metal impurity. The addition of the dopant atoms in CdS turns it into a p-type semiconductor. This half metallic character makes these compounds a potential candidate for spintronics applications. In optical properties, the role of Mn concentration on the absorption coefficient, optical conductivity, refractive index, extinction coefficient and dielectric function has been investigated. The total magnetic moment is found approximately 5.000 μB per dopant atom for Cd1−xMnxS (x = 6.25%, 12.5% and 25%). This value indicates that every Mn impurity adds no hole carriers to the perfect CdS crystal. [ABSTRACT FROM AUTHOR]

A series of pentagonal bipyramidal anionic germanium clusters doped with heavy rare earth elements, REGe 6 - (RE = Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu), have been identified at the PBE0/def2-TZVP level using density functional theory (DFT). Our findings reveal that the centrally doped pentagonal ring structure demonstrates enhanced stability and heightened aromaticity due to its uniform bonding characteristics and a larger charge transfer region. Through natural population analysis and spin density diagrams, we observed a monotonic decrease in the magnetic moment from Gd to Yb. This is attributed to the decreasing number of unpaired electrons in the 4f orbitals of the heavy rare earth atoms. Interestingly, the system doped with Er atoms showed lower stability and anti-aromaticity, likely due to the involvement of the 4f orbitals in bonding. Conversely, the systems doped with Gd and Tb atoms stood out for their high magnetism and stability, making them potential building blocks for rare earth-doped semiconductor materials., (© 2024 Wiley Periodicals LLC.)

We have searched for exotic neutrino-electron interactions that could be produced by a neutrino millicharge, by a neutrino magnetic moment, or by dark photons using solar neutrinos in the XMASS-I liquid xenon detector. We observed no significant signals in 711 days of data. We obtain an upper limit for neutrino millicharge of 5.4×10−12e at 90% confidence level assuming all three species of neutrino have common millicharge. We also set flavor-dependent limits assuming the respective neutrino flavor is the only one carrying a millicharge, 7.3×10−12e for νe, 1.1×10−11e for νμ, and 1.1×10−11e for ντ. These limits are the most stringent yet obtained from direct measurements. We also obtain an upper limit for the neutrino magnetic moment of 1.8×10−10 Bohr magnetons. In addition, we obtain upper limits for the coupling constant of dark photons in the U(1)B−L model of 1.3×10−6 if the dark photon mass is 1×10−3 MeV/c2, and 8.8×10−5 if it is 10 MeV/c2.

Magnetic field and eddy currents in a cylinder of finite length are calculated by separation of variables. The magnetic field outside the cylinder or inside the bore of the hollow cylinder and shell is expressed in terms of Bessel functions. Both axial and transverse applied fields are considered for the solid and hollow cylinders. The equations for the vector potential components are transformed in one-dimensional equations along the radial coordinate with the consequent integration by the method of variation of parameters. The equation for the scalar electric potential when required is also integrated analytically. Expressions for the magnetic moment and loss are derived. An alternative analytical solution in terms of scalar magnetic potential is derived for the finite length thin shells. All formulas are validated by the comparison with the solutions by finite–element and finite-difference methods.

Electronic, optical and magnetic properties of perovskite oxides PrXO3(X = V, Cr) are calculated by first-principle calculations. The calculations of electronic band structure and density of states (DOS) show that the PrVO3 exhibits metallic behaviour, while PrCrO3 exhibits half-metallic nature with direct band gap. The calculated band gap of PrCrO3 is 2.7 in the minority spin state. The origin and nature of ferromagnetism has been observed in terms of crystal field energies, exchange constant and exchange energies. The magnetic moment of PrVO3 is 3.42491 μB, while that of PrCrO3 is 5.00003 μB. Moreover, the evolution of PrCrO3 compound based on its electronic and magnetic properties confirms that the compound is suitable for spintronics applications. Results revealed that PrCrO3 has low reflectivity, high dielectric constant, high optical conductivity and high absorption coefficient which indicate that the material is a potential candidate in the wide range of optoelectronic applications. [ABSTRACT FROM AUTHOR]

The magnetic moment of the molybdenum disulfide monolayer (MoS2) is calculated in the presence of a perpendicular magnetic field B. The field B leads to a significant increase in the spin splitting in the conduction band, which is reflected in the expression of the magnetic moment. The oscillatory character of the magnetic moment dependences on the magnetic field is investigated. [ABSTRACT FROM AUTHOR]

The magnetic moment of the unmodulated bilayer graphene is calculated in the presence of a perpendicular magnetic field B. The oscillatory character of the magnetic moment dependences on the magnetic field is investigated. [ABSTRACT FROM AUTHOR]

The spinel oxides SnV2O4 and SnCr2O4 are analysed to reveal the mechanical, electronic and magnetic properties using Wien2k software. The negative formation energy and positive elastic constants shows the studied materials are thermodynamically and mechanically favorable. In ferromagnetic (FM) state more energy release than antiferromagnetic (AFM) state. The above room temperature magnetism is elaborated by spin polarisation, exchange mechanism, direct Δx(d) and indirect Δx(pd) exchange energy and crystal field energy Δx(CF). The shifting of magnetic moment form V/Cr sites to Sn/V sites illustrate the ferromagnetism is caused by pd hybridisation that affects the net orientation of electrons spin and hence, it increases the importance of the materials for spin-dependent electronic applications. [ABSTRACT FROM AUTHOR]

First-principles calculations of density functional theory (DFT) using the generalized gradient approximation (GGA) and generalized gradient approximation with the Hubbard U (GGA + U) for the exchange-correlation energy functional are used to investigate the structural, electronic, and magnetic properties of the spinel system C d x N i 1 − x F e 2 O 4 in the range 0 ≤ x ≤ 1. High-temperature series expansions (HTSE) combined with the Padé approximants (PA) method and mean field theory (MFT) are applied to the C d x N i 1 − x F e 2 O 4 systems. The lattice parameter and magnetic moment of Fe and Ni ions increase when Cd content x increases. Density of States (DOS) calculations show that the C d x N i 1 − x F e 2 O 4 has a semiconductor behaviour. The obtained theoretical results show that the Curie temperature decreases with x. These obtained results are in agreement with experimental ones. [ABSTRACT FROM AUTHOR]

Based on the full-potential linearised augmented plane wave plus local orbitals (FP-L/APW + lo) method within the density functional theory (DFT), the structural, electronic, and magnetic calculations of the cubic oxide perovskite NdInO3 compound have been done under the generalised gradient approximation (GGA). The exchange and correlation (XC) potential is defined as GGA framework in the analyses of structural properties, while both GGA and GGA + U (U is the Hubbard correlation term) approximations are taken to treat the electronic and magnetic properties. It is found that ferromagnetic (FM) configuration is reported as the most stable ground state of the cubic NdInO3 material; however, the equilibrium lattice parameters such as lattice constant (a0), bulk modulus (B0), its first-pressure derivative (B'), and the minimum of total energy (E0) are given in paramagnetic (PM), ferromagnetic (FM), and anti-ferromagnetic (AFM) states. The spin-polarized electronic structure calculations (band structure and density of states) of the cubic oxide perovskite NdInO3 compound verify the half-metallic feature due to the spin-up case which has the metallic nature, whereas the spin-down case presents the semiconducting character. Moreover, the magnetic properties show the integer value of the total magnetic moment for the studied compound (3μB), where it is manly contributed by Nd atoms with apparition of weak local magnetic moments in non magnetic In and O sites. [ABSTRACT FROM AUTHOR]

Ab initio calculations were systematically investigated for nonmagnetic (NM), ferromagnetic (FM), and antiferromagnetic (AFM) states of new full-Heusler alloy Cr2MnSi in Hg2CuTi and Cu2MnAl-type structures. The calculations are based on the density functional theory, with the full potential linear muffin-tin orbital (FP-LMTO) method. The results show that the ferromagnetic Hg2CuTi prototype structure is the most stable. The optimized lattice parameter is found to be 5.643 Å, with the total magnetic moment 0.30 μB. The electronic band structure calculations revealed that Cr2MnSi exhibits a metallic ferromagnet behavior. Using the Mehl method, we have also calculated the elastic constants and their related parameters such as Poisson's ratio, Young modulus, Zener anisotropy, shear modulus, Kleinman parameter ξ, Lamé constants (λ, μ), Cauchy pressure Pc, microhardness parameter, and the melting temperature Tm. Our calculation validates the conditions of mechanical stability in the cubic crystal. The estimation of the Curie temperature shows that the Cr2MnSi compound is a good candidate for the spintronic application. [ABSTRACT FROM AUTHOR]

Based on the full-potential linearised augmented plane wave plus local orbitals (FP-L/APW + lo) method within the density functional theory (DFT), the structural, electronic, and magnetic calculations of the cubic oxide perovskite NdInO3 compound have been done under the generalised gradient approximation (GGA). The exchange and correlation (XC) potential is defined as GGA framework in the analyses of structural properties, while both GGA and GGA + U (U is the Hubbard correlation term) approximations are taken to treat the electronic and magnetic properties. It is found that ferromagnetic (FM) configuration is reported as the most stable ground state of the cubic NdInO3 material; however, the equilibrium lattice parameters such as lattice constant (a0), bulk modulus (B0), its first-pressure derivative (B'), and the minimum of total energy (E0) are given in paramagnetic (PM), ferromagnetic (FM), and anti-ferromagnetic (AFM) states. The spin-polarized electronic structure calculations (band structure and density of states) of the cubic oxide perovskite NdInO3 compound verify the half-metallic feature due to the spin-up case which has the metallic nature, whereas the spin-down case presents the semiconducting character. Moreover, the magnetic properties show the integer value of the total magnetic moment for the studied compound (3μB), where it is manly contributed by Nd atoms with apparition of weak local magnetic moments in non magnetic In and O sites. [ABSTRACT FROM AUTHOR]

In magnetic anomaly detection, it is a prerequisite to master the far-field magnetic moment vector information of the target. It is important to measure the magnetic moment of the target in target location, recognition and degaussing. In the paper, we proposed a method of measuring the magnetic moment vector of the target based on the total geomagnetic field. In this method, a sensor array with the scalar magnetometers was constructed and the quantitative factors of the magnetometer were analyzed. In order to eliminate the time-varying and uneven spatial distribution of geomagnetic total field, a double gradient algorithm was applied to magnetic moment measurement in this method. And a criterion function of determining the magnitude and direction of the target magnetic moment was defined. The proposed method was validated by the theoretical calculation and real experimental data. The results showed that the measured magnetic field data were qualitatively in good agreement with the theoretical curve. For the magnitude of magnetic moment, the average relative deviation was 5.1%. And the average relative deviation of inclination and declination of the moment were 3.2% and 2.5%, respectively. In addition, we attempted to separate the induced magnetic moment and the intrinsic magnetic moment of the target. The proposed method can be used as a reference for the target magnetic location and demagnetization. [ABSTRACT FROM AUTHOR]

In this manuscript, we discussed an ab initio analysis of the structural, electronic, optical and magnetic properties of LnO (Ln = Eu, Dy) compounds. Our assessments were performed by the augmented plane wave method FP LAPW founded on the DFT (density functional theory) and introduced in the Wien2k calculation code. This investigation of the electronic band, structural, optical and magnetic properties were performed using a combination of modified Becke–Johnson exchange potential plus GGA + U-mBJ for exchange-correlation potential. In our study, the ferromagnetic behavior of the two compounds is very clear with magnetic moments of around 7 µB for EuO and 5 µB for DyO. The structure transitions for these materials from B1 to B2 are possible at high pressures and the calculation of the band structure shows that DyO has a direct gap (X–X). [ABSTRACT FROM AUTHOR]

The Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) complexes of isoniazid (L1) mixed with 2,2-bipyridine (L2) were synthesized and characterized by solubility studies, percentage metal analysis, UV-Vis spectroscopy, IR spectroscopy, conductivity measurements and magnetic moment measurements. The IR spectra revealed that the isoniazid coordinated as a bidentate ligand. In Co(II) and Ni(II) complex it coordinated via the carbonyl oxygen (C=O) and the amide nitrogen, while in the Cu(II), Mn(II) and Zn(II) complexes it coordinated using the amide and carbonyl oxygen via enolization. Bipyridine also bonded to the metals as a bidentate ligand through the pyridinic nitrogen atoms. The magnetic data showed that all the complexes were paramagnetic with values ranging from 1.70 to 5.0 B.M., except [Zn(Is)(Bipy)(H2O)Cl2] which was diamagnetic. The conductivity results revealed that the Cu(II), Mn(II), Zn(II) complexes were 1:1 electrolytes while Co(II) was 1:2 electrolyte and [Ni(Is)(Bipy)Cl2] was non-electrolytic in nature. The antibacterial activities of the ligands and the complexes as evaluated via the agar diffusion method showed that the complexes displayed moderately high antimicrobial activity in comparison with the free ligands when tested against ten strains of bacteria. [ABSTRACT FROM AUTHOR]

Employing light-cone QCD sum rule, we have acquired the magnetic moment of the Zc(3900) resonance by considering it as the molecular form of * DD and * D Dresonance with quantum numbers JPC = 1+-. The magnetic moment contains crucial knowledge about the internal organization of particles and their geometric configuration. Measurement of the magnetic moment of the Zc(3900) resonance in future experiments can be quite useful comprehension the inner organization of exotic resonances. A comparison of our numerical values on the magnetic moment with those estimated by the other theoretical models existing in literature is carried out. [ABSTRACT FROM AUTHOR]

Transition metal chalcogenides (TMCs) nanomaterials have become of great scientific interest due to unusual physical and chemical properties and the useful technological applications. Here, we have studied the effect of different transition metal (TM) doping on the structural, electronic, magnetic, and vibrational properties of Ten (n = 6, 8, 10, and 12) clusters using density functional theory calculations. We notice that out of different doped clusters, the one with n = 10 exhibits the lowest symmetry. However, all the doped clusters have planner structure similar to pristine Ten clusters. The calculation of vibrational frequencies along with Raman spectra reveals the unstable nature of TM@Te6 clusters reflected via the observation of imaginary vibrational frequencies. Interestingly, we observe that binding energy per atom for TM@Ten clusters is more than Ten and the eigenvalue spectrum of TM@Ten reveals that the transition metal energy levels lie between Te energy levels. The accumulation of charge around the transition metals indicates their more electronegative nature. Additionally, significant quenching of magnetic moment is observed in Ni-doped Ten clusters. In order to understand the microscopic origin of magnetic properties, we have done a detailed analysis of local magnetic moment associated with different atoms along with projected density of states (PDOS). [ABSTRACT FROM AUTHOR]

An original magnetometer based on a dc superconducting quantum interferometer is described. The design features of the device are discussed and functional diagrams of its new units are presented. The magnetic moment measurement methods that optimize the measurement process are proposed. Examples of the investigations carried out on the samples of different materials are given. The factors affecting the reliability of the magnetic measurements are considered. [ABSTRACT FROM AUTHOR]

Ferromagnetic rare‐earth‐based inverse perovskites Gd3AlX (X = B, N) are studied using hybrid functionals in the framework of density functional theory. Different exchange correlation potentials are employed to analyze the structural parameters and geometry of the materials. The spin polarization and band structure explain the metallic behavior of these materials with high values of magnetic moment. The calculated elastic constants specify all materials are ordered perovskite compounds, among which Gd3GaB, Gd3GaN, Gd3InN are brittle in nature while as Gd3InB is ductile in nature. The quasi‐harmonic Debye model was used to predict the thermodynamic properties of the material. The analysis of thermoelectric properties viz. Seebeck coefficient, electronic and thermal conductivities at higher temperature has been carried out. To check the optoelectronic response of the material various optical properties have been calculated up to 14 eV photon energy range. The competent thermoelectric and optoelectronic properties with high value of magnetic moment and ductile character suggests the application in thermoelectric and electro‐optic devices. [ABSTRACT FROM AUTHOR]

Synthesis of tetradentate Schiff base (SB) complexes of Cu(II), Co(II), and Ni(II) was done by the condensation of 2-aminophenol/o-phenylenediamine and terepthaldehyde in an alcohol medium, and the complexes were characterized by utilizing FTIR, LCMS, and UV–visible analysis. From the analytical, electronic, and magnetic data, octahedral geometry has been proposed for all the complexes. The antibacterial studies were studied for the SB ligands and their complexes against Bacillus subtilis 2393, Proteus vulgaris 426, Klebsiella sp., S. aureus 3160, and Escherichia coli 4604. Their antifungal activities were studied against Aspergilus flavus, Aspergillus niger, Cryptococcus neoformans, and Penicillium chrysogenum. The outcomes revealed that the transition metal complexes revealed good antibacterial and antifungal activities. [ABSTRACT FROM AUTHOR]

The results of ab-initio calculations of the electronic structure and magnetism of the new superconductor RbEuFe 4 As 4 are reported. The electronic band structure and the density of states are presented and discussed in detail. The electric charge density distributions along different crystallographic planes are presented, and the origin of the chemical bonding between the constituent atoms is discussed in detail. The evidence is provided for the existence of a mixture of ionic, covalent, and metallic bonding. It is demonstrated that the magnetic moment is mainly due to the strongly localised Eu 4 f states. An almost negligible magnetic moment carried by the Fe atoms is shown to be due to the symmetry of the Fe spin-up and spin-down states. It is demonstrated that the electrical and chemical properties of RbEuFe 4 As 4 are closely linked with the presence of the Fe 3 d states in the Fermi energy region. The Fermi surfaces show the presence of hole-like and electron-like pockets, respectively, at the center and corners of the Brillouin zone. The results of the calculations of the elastic properties and the 57 Fe and 151 Eu hyperfine-interaction parameters are also presented. [ABSTRACT FROM AUTHOR]

Creating a single-carbon vacancy introduces (quasi-)localized states for both σ and π electrons in graphene. Theoretically, interactions between the localized σ electrons and quasilocalized π electrons of a single-carbon vacancy in graphene are predicted to control its magnetism. However, experimentally confirming this prediction through manipulating the interactions remains an outstanding challenge. Here we report the manipulation of magnetism in the vicinity of an individual single-carbon vacancy in graphene by using a scanning tunnelling microscopy (STM) tip. Our spin-polarized STM measurements, complemented by density functional theory calculations, indicate that the interactions between the localized σ and quasilocalized π electrons could split the π electrons into two states with opposite spins even when they are well above the Fermi level. Via the STM tip, we successfully manipulate both the magnitude and direction of magnetic moment of the π electrons with respect to that of the σ electrons. Three different magnetic states of the single-carbon vacancy, exhibiting magnetic moments of about 1.6 μ B , 0.5 μ B , and 0 μ B respectively, are realized in our experiment. [ABSTRACT FROM AUTHOR]

The structures, spectra and electronic and magnetic properties of Ag4M and Ag4MCO (M = Sc–Zn) clusters have been studied using density functional theory and CALYPSO structure searching method. Structural searches show that M atoms except Zn tend to occupy the highest coordination position in the ground state Ag4M and Ag4MCO clusters. Carbon monoxide is most easily adsorbed on Ag atom of Ag4Zn and M atom of other Ag4M. Infrared and Raman spectra, photoabsorption spectra and photoelectron spectra of Ag4M and Ag4MCO clusters are forecasted and can be used to identify these clusters from experiment. Analysis of electronic properties indicates that the adsorption of CO on Ag4M clusters changes the zero vibrational energy (ZPVE) and increases stability of the host clusters. Dopant atoms except for Zn improve the stability of silver cluster. The Ag4Ni cluster shows high chemical activity and maximum adsorption energy for carbon monoxide. Magnetism calculations reveal that the magnetic moment of Ag4M (M = Mn–Ni) cluster adsorbed by carbon monoxide is decreased by 2 μB. The change of magnetic moment makes it possible to be used as a nanomaterial for carbon monoxide detection. Simultaneously, it is found that the adsorption of CO on Ag4Cu cluster is a physical adsorption. [ABSTRACT FROM AUTHOR]

Structural, electronic and magnetic properties of the neutral and ionic Nin−1X (X = C, Si, Ge, Sn, Pb; n = 19–23) clusters have been investigated using the density functional theory calculations with the PBE exchange–correlation energy functional. The calculations have shown that for the most stable structures of all Nin−1X clusters, only Si atom prefers to locate in the center position, while for the other atoms, the impurity usually adopts the surface position. Based on the most stable Nin−1X clusters, the properties including binding energy per atom, embedding energy, charge transfer, ionization potentials, electron affinities and especially magnetic properties have been discussed. [ABSTRACT FROM AUTHOR]

Zn 0.95 V 0.05 O ceramics, elaborated from milled ZnO and V 2 O 5 nanopowders, were sintered at 900, 1000 and 1100 °C for 1, 2, 4, 6, 10 and 14 h. The growth kinetics was studied identifying the grain growth exponent, the activation energy and the pre-exponential factor. The high V 2 O 5 concentration allowed a rapid grain growth at 900 °C only at the very first stages (t < 1 h). Meanwhile, at temperatures of 1000 and 1100 °C, the grain growth was extremely fast with a growth exponent of 0.72. The magnetic properties of the samples indicate that ferromagnetism exist in all samples in different magnitudes depending on the sintering conditions. In particular, the maximum magnetization was obtained on the sample sintered at 1100 °C for 14 h, despite the reduction of V concentration. Additionally, secondary paramagnetic phases were detected in the samples sintered at lower temperatures and shorter sintering times. [ABSTRACT FROM AUTHOR]

The lowest energy structure of Li15 cluster is a capped double centred square antiprism sharing a square face. Interestingly, when a lithium atom is substituted by a transition-metal atom TM (TM = Sc, Ti, V, Y, Zr, Nb, Hf, Ta and W), the lowest energy structure is found to be cage-like with a D6d symmetry, where the outer cage is composed by fourteen lithium atoms with an endohedral transition-metal atom. The unique structures are confirmed by CALYSPO structure prediction method code and density-functional theory calculations. Superatomic properties are confirmed in all the D6d clusters. Energy calculations predict that they are very stable, and their stability is further enhanced by the large gaps of the highest occupied molecular orbital and the lowest unoccupied molecular orbital (HOMO–LUMO gaps). Our findings offer potential applications in building blocks for assembling materials with superatoms. [ABSTRACT FROM AUTHOR]