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K20 microwave dielectric ceramics SrLnAlO 4 (Ln = Eu, Gd, and Ho) were prepared at 1440–1520 °C. SrEuAlO 4 and SrGdAlO 4 crystallized into tetragonal K 2 NiF 4 -type structures. While SrHoAlO 4 was a mixture (SrHo 2 Al 2 O 7 , Ho 2 O 3 , and Sr 3 HoAl 2 O 7.5) due to the too-small radius of Ho3+ to bond in [HoO 9 ] dodecahedron. SrEuAlO 4 and SrGdAlO 4 exhibited near-zero τ f values of +1.7 and +4.3 ppm/°C and low ε r (19.37 and 19.14) along with contrasting Q × f values (70,030 and 5560 GHz). Compared with the modified molecular polarizability (α Corr) based on the bond valence deviation, the α obs values of SrEuAlO 4 and SrGdAlO 4 are much higher, indicating that their dielectric polarizabilities were underestimated, and this phenomenon was mainly influenced by rattling cations, which also causes their τ f with near-zero values. Due to the magnetic subsystem adversely affecting microwave dielectric losses, the worsened Q × f value of SrGdAlO 4 compared to that of SrEuAlO 4 is due to the high magnetic moment of Gd3+ (7.94 μ B). [ABSTRACT FROM AUTHOR]

The structural stability, electronic structure, and optical properties of the novel YxGd1-xN ternary alloys were studied using the FP-LAPW method with the generalized gradient approximation + Hubbard U (GGA + U). Our results reveal that YxGd1-xN alloys can be experimentally synthesized because they exhibit energetic and mechanical stability. All these systems present semiconducting behavior. Both GdN and YN are indirect band gap semiconductors while YxGd1-xN alloys are direct band gap semiconductors for $x = 0.25\comma \; 0.5\comma \; 0.75$x=0.25,0.5,0.75 because of hybridization between d (Y) and Gd(f) orbitals in the vicinity of the Fermi energy level. The f-d coupling induces the major magnetic moments on the Gd atom. The absorption spectra are reasonably high (>105 cm−1) and the bandgap energy and structure spacing match between YN and GaN which made YxGd1-xN alloys suitable for optoelectronic applications. In the absence of experimental work, our results can be useful for further studies. [ABSTRACT FROM AUTHOR]

This study presents an unmanned aerial vehicle (UAV)-borne vector magnetometer (MAG) system and proposes a new data-processing technique for modeling the residual magnetic anomalies of three types of landmines: the metallic antitank M15, the metallic antipersonnel M16, and the minimum-metal antitank M19. The burial depth and magnetic moment of these landmines were estimated using the measured and simulated residual magnetic anomalies based on the proposed UAV-borne vector MAG model. Initial in-flight validation showed a strong correlation between the residual magnetic anomaly maps obtained from measurements and simulations. To verify the detection capability in real-world conditions, the UAV-borne MAG system was tested at the Korean Combat Training Center. Both simulations and experiments demonstrated the effectiveness of the proposed data-processing method and UAV-borne MAG model in accurately modeling the residual magnetic anomalies of landmines with metallic components. This approach will facilitate the automated detection of M15, M16, and M19 landmines with high detection rates and enable accurate classification. [ABSTRACT FROM AUTHOR]

Solar cells are currently the focus of a great deal of research. The aim is to reduce their cost price. To achieve this, we need to reduce the mass of the materials and increase the conversion efficiency of these solar cells. This has motivated research into the use of thin films such as a-Si, CdTe, CIGS. This increase in efficiency requires optimizing the performance of the photovoltaic parameters. In this modeling and simulation work, we use the SCAPS-1D software to study the effect of the recombination speed of the electrons and holes in the CIGS layer, the effect of the thickness of the layers and the effect of the gap energy of each layer of the material used for this solar cell on the short-circuit current Jsc, the open-circuit voltage Voc, the form factor FF and the electrical efficiency η of the CIGS cell for a Mo/p-CIGS/p-Si/In2S3/i-ZnO/Al-ZnO single-junction structure. In this study, we found that recombination speed affects the efficiency of the photovoltaic cell. The gap energy of the absorber layers influences the cell's efficiency, while the other layers (In2S3, ZnO, Al-ZnO) do not have a great influence on solar cell performance and increasing the thickness of the absorber layer has a major influence on efficiency, increasing it up to a certain limit. The thicknesses of the CIGS, p-Si, In2S3, i-ZnO and Al‑ZnO layers need to be in the order of 0.3µm, 0.8µm, 0.05µm, 0.07µm and 0.1µm respectively to achieve better efficiency (31.42%).

A series of pentagonal bipyramidal anionic germanium clusters doped with heavy rare earth elements, REGe6− (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. [ABSTRACT FROM AUTHOR]

In the presented work, we propose a systematic investigation of the electronic and optical properties of MnGa2Se4 by combining the spectroscopic ellipsometry carried out at room temperature in the spectral range of 1–4 eV and density functional theory (DFT) calculations. Ellipsometric measurements were collected at an incidence angle between 60° and 75° with a 5° step. The optical direct gap energies of MnGa2Se4 were estimated from the linear extrapolation of the absorption coefficients that were verified by band structure calculation. DFT calculation of the imaginary part ɛ shows that first critical point occurs at 2.46 eV and represents the direct optical transition at Γ point. The total magnetic moment of compound is 3.38 mB. The major contribution in total magnetic moment is due to 3d state of Mn atoms. [ABSTRACT FROM AUTHOR]

In the presented work, we propose a systematic investigation of the electronic and optical properties of MnGa2Se4 by combining the spectroscopic ellipsometry carried out at room temperature in the spectral range of 1–4 eV and density functional theory (DFT) calculations. Ellipsometric measurements were collected at an incidence angle between 60° and 75° with a 5° step. The optical direct gap energies of MnGa2Se4 were estimated from the linear extrapolation of the absorption coefficients that were verified by band structure calculation. DFT calculation of the imaginary part ɛ shows that first critical point occurs at 2.46 eV and represents the direct optical transition at Γ point. The total magnetic moment of compound is 3.38 mB. The major contribution in total magnetic moment is due to 3d state of Mn atoms. [ABSTRACT FROM AUTHOR]

New (Er1 –xYx)0.8Sm0.2Fe2 multicomponent alloys with a substitution parameter of x = 0, 0.2, 0.4, 0.6, 0.8, and 1.0 are synthesized and their atomic crystal structure and magnetic properties are studied. It is shown that full magnetic compensation can be expected in the region of 0.2 < xcomp < 0.4. Er0.8Sm0.2Fe2 alloy exhibits temperature-dependent magnetization compensation at Tcomp = 400 K. [ABSTRACT FROM AUTHOR]

In this study, a new evaluation method was investigated for the magnetic properties of the amorphous alloys by comparing the experimental results with the theoretical calculations. First, The (Fe70Co6P4.8Si9.6B9.6)100−xCux (x=0–0.5) amorphous ribbons were prepared by melt spinning method. Then, the magnetic properties of the prepared amorphous alloys were measured as 165.86–147.04emu/g, respectively. On the other side, we analyzed the valence electron structure and obtained the magnetizations as 159.92–158.77emu/g by calculating the magnetic moments of unit cells based on empirical electron theory (EET) of solids and molecules. Through comparing the magnetic properties of the calculations with the measurements, we found that the differences between the calculations and the measurements are less than 12% for all samples, meeting the first approximation requirement. Moreover, with the addition of Cu, the change trends both in the calculated and measured magnetic properties are also consistent. These results prove that it is feasible to calculate the magnetic property of the amorphous alloy from the valence electron level using EET, which provides a new method to investigate the soft magnetic property of the amorphous alloy instead of the real measurement. [ABSTRACT FROM AUTHOR]

Device applications in magnetic media, spintronics, oxygen membranes, sensors, etc., are some of the uses of ferrite materials. In this work, we have studied the structural, electronic, magnetic, mechanical, and thermoelectric properties of Cs-based double perovskites Cs2AX6 (A = Ge, Mn; X = Cl, I), using Quantum Espresso with generalized gradient approximation Perdew-Burke-Ernzerhof and Perdew-Burke-Ernzerhof in solids exchange-correlation functionals. The band structure results show that Cs2GeCl6 and Cs2MnCl6 are semiconductors with direct band gaps. However, there are bands crossing observed for Cs2GeI6 from the conduction band minimum to the valence band maximum, indicating the metallic nature of the material. Moreover, Cs2MnI6 has magnetic properties; it exhibits a metallic nature in the spin-up state and a semiconductor nature in the spin-down state, suggesting that it can be used in spintronics applications. The calculated total magnetic moment of Cs2MnCl6 is 3:0μB (for both Perdew-Burke-Ernzerhof and Perdew-Burke-Ernzerhof in solids), while for Cs2MnI6, the calculated total magnetic moments are 3:02μB and 3:06μB, for Perdew-Burke-Ernzerhof and Perdew-Burke-Ernzerhof in solids exchange-correlation functionals, respectively. The results of the mechanical properties calculations show that Cs-based double perovskites Cs2AX6 (A = Ge, Mn; X = Cl, I) are mechanically stable. Cauchy's pressure and Poisson's, Frantsevich's, and Pugh's ratios of the studied materials confirm that Cs2MnCl6 is brittle, while the remaining studied double perovskite materials are ductile. Electrical conductivity, thermal conductivity, Seebeck coefficients, power factor, and figure of merit are the thermoelectric parameters analyzed in this study. Seebeck coefficients, electrical conductivity, and power factor increase with the rise in temperature, and Cs2MnX6 (X = Cl, I) double perovskite materials have higher values of electrical conductivity than Cs2GeX6 (X = Cl, I). All the studied materials have positive type conductivity due to their positive Seebeck coefficient values. [ABSTRACT FROM AUTHOR]

The transient radiation of the magnetic moment in the plane-layered medium is considered. In order, to determine the electromagnetic field of the magnetic moment, in contrast to the known method of the field vectors, for the first time, the electric and magnetic Hertzian vectors are introduced as initial functions which turns out to be the most efficient for calculating the field amplitudes. This method can also be applied to calculate the field and power of the Cherenkov radiation of a charged particle with a magnetic dipole moment. The expressions are obtained for the Eigen field and the radiation field of a magnetic moment moving in media whose permittivity changes smoothly in the direction of motion. The radiation fields are estimated and the contribution of the magnetic transient radiation to the radiation of the particle is found. In particular, it is shown that in the interplanetary medium (in the ionosphere) the contribution of magnetic transient radiation becomes more significant in the ultra-relativistic case, in the region of small angles. The obtained results can be considered at the development of the devices for registration and identification of easy charged particles, having the magnetic moment: transient radiation detectors, and also for definition of transient radiation role in earth atmosphere and earth core, which are considered as plane-layered ones. [ABSTRACT FROM AUTHOR]

The anomalous magnetic moment of the electron, first calculated by Schwinger, lowers the ground state energy of the electron in a weak magnetic field. It is a function of the field and changes signs for large fields, ensuring the stability of the ground state. This has been shown in the past 50 years in numerous papers. The corresponding corrections to the mass of the electron have also been investigated in strong fields using semiclassical methods. We critically review these developments and point out that the calculation for low-lying excited states raises questions. Also, we calculate the contribution from the tadpole diagram, the relevance of which was observed only quite recently.

In this study, the electronic and magnetic properties of hydrogen-passivated armchair and zigzag GaN nanoribbons are investigated using density-functional theory. We explore that doped TM atom leads to additional levels in the band gap and thus plays an essential role in spin polarization and changes their properties. Depending on its location in the nanoribbon, the character of spin-dependent electronic property of a doped GaN-NR was analyzed. Our calculations show that, regardless of the position of Mn atoms, GaNNTs are stable in ferromagnetic phase. [ABSTRACT FROM AUTHOR]

Based on the equations of electrodynamics and the concept of a critical state for hard superconductors of the 2nd kind, numerical simulation of the magnetic properties of axisymmetric superconducting samples, in particular, granules, is performed for a number of models of the dependence of the critical current density on the magnetic field induction. The magnetic moment loops are calculated directly by integrating the integral equation for the current density over time. The phenomena of the peak effect and the asymmetry of the magnetization hysteresis loop are also considered using the indicated equation. Various versions of the functions used in the literature were used as peak functions. In addition to the hysteresis loop of the magnetic moment, the magnetic field induction at the center of axisymmetric samples, and the total penetration field, the profiles of the critical current density Jc(B) and the equilibrium magnetic moment for spherical granules were obtained. The method used for calculating the magnetic moment of superconductors makes it possible to take into account the equilibrium and nonequilibrium regions of the magnetization of the samples independently. [ABSTRACT FROM AUTHOR]

The anomalous magnetic moment of the electron, first calculated by Schwinger, lowers the ground state energy of the electron in a weak magnetic field. It is a function of the field and changes signs for large fields, ensuring the stability of the ground state. This has been shown in the past 50 years in numerous papers. The corresponding corrections to the mass of the electron have also been investigated in strong fields using semiclassical methods. We critically review these developments and point out that the calculation for low-lying excited states raises questions. Also, we calculate the contribution from the tadpole diagram, the relevance of which was observed only quite recently. [ABSTRACT FROM AUTHOR]

We investigated the magnetic and thermoelectric properties of REMoN3 (RE = La, Ce, Pr, Nd, Sm) perovskites using the full potential linearized augmented plane wave (FP‐LAPW) method. To overcome the problem of underestimation of electronic interaction, we employed the DFT + U approach to accurately map the electronic structure of these compounds. Our study shows an increasing trend in the magnetic moments with the increasing number of unpaired electrons in RE. Among these compounds, SmMoN3 possesses a large magnetic moment, which is suitable for applications such as memory devices and sensors. Interestingly, all these perovskites display ferromagnetic behavior except CeMoN3, which exhibits an antiferromagnetic nature. Furthermore, our analysis indicates n‐type thermoelectric behavior in all these materials. The compound, namely PrMoN3, exhibits a high figure of merit among REMoN3, which can be improved by modifying the lattice sites. [ABSTRACT FROM AUTHOR]

The interaction between sites A, B and X with passivation molecules is restricted when the conventional passivation strategy is applied in perovskite (ABX3) photovoltaics. Fortunately, the revolving A-site presents an opportunity to strengthen this interaction by utilizing an external field. Herein, we propose a novel approach to achieving an ordered magnetic dipole moment, which is regulated by a magnetic field via the coupling effect between the chiral passivation molecule and the A-site (formamidine ion) in perovskites. This strategy can increase the molecular interaction energy by approximately four times and ensure a well-ordered molecular arrangement. The quality of the deposited perovskite film is significantly optimized with inhibited nonradiative recombination. It manages to reduce the open-circuit voltage loss of photovoltaic devices to 360 mV and increase the power conversion efficiency to 25.22%. This finding provides a new insight into the exploration of A-sites in perovskites and offers a novel route to improving the device performance of perovskite photovoltaics. [ABSTRACT FROM AUTHOR]

Pearlite is one of the fundamental structural components of carbon and low-alloy steels. In pearlite, the orientation relationships of Bagaryatsky, Isaychev, and Pitsch can be observed between the body-centered cubic ferritic and rhombic cementite Fe3C phases. In low-temperature pearlite, which exhibits the highest strength, the first two predominate, and they are closely related, sometimes indistinguishable in experiments. In this study, ab initio simulation using density functional theory in the WIEN2k software package is conducted to investigate the structures and energies of coherent α-Fe/Fe3C interphase boundaries. The supercells undergo structural and volume optimization. Calculations of the interphase boundary surface energy yield values of 0.383 and 0.594 J/m2 for the Bagaryatsky and Isaychev orientation relationships, respectively. These results align well with existing experimental values and outcomes from other molecular dynamics and ab initio calculations. The difference in the surface energy may play a significant role in low-temperature pearlite with thin plates of ferrite and cementite and a large interphase-boundary area per unit volume. [ABSTRACT FROM AUTHOR]

First-principles calculations, using density functional theory, have been studied to investigate the sensing of NO2, NO, N2, CO2, CO, O2, NH3 and SO2 gases on bare and Fe-doped antimonene armchair nanoribbons (Fe-doped ASbNRs). The sensing behaviors of these gases on bare and Fe-doped ASbNRs have been analyzed in terms of band structure, the density of states, adsorption energy, charge transfer, magnetic moments and I–V characteristics. We showed that doping the magnetic Fe atom increases the sensing ability of antimonene nanoribbon where the gas molecules are chemisorption on Fe-doped ASbNR. This chemisorption induces dramatic change in the adsorption energy and electronic structures, and injects magnetic moments into the nanoribbon system. The NO molecule depicts the tightest binding in the Fe-doped ASbNRs. Charge transfer analysis of adsorbates demonstrates that all gas molecules, except NO, NH3 and CO are electron donors to nanoribbon. Transport properties of Fe-doped ASbNRs transistor, display desirable I–V characteristics and spin filter efficiency for the NO2, N2, and NH3 gases. These two-dimensional systems may possess the potential in the promising application of gas sensing. [ABSTRACT FROM AUTHOR]

The focus of this study is the structural, electronic, and magnetic characteristics of the ZnSeTe solid solution with chromium impurity. The structure of this solid solution was determined in two steps. At the first stage the internal coordinates of atoms are optimized, and at the second one the lattice parameter relaxation, including re-optimization of internal coordinates, were done. Further, after the introduction of Cr substitution impurity, electronic energy spectra and densities of electronic states were calculated. Significant changes in parameters of the electronic structure and magnetic properties caused by cationic vacancy were revealed. It was found that the doped solid solution of Cr:ZnSeTe is a semiconductor for both electron spin polarizations. The study of the supercell with a cationic vacancy revealed significant differences in the parameters of electronic energy bands as well as magnetic properties, compared with those in crystal with no defects. [ABSTRACT FROM AUTHOR]

The calculation of the magnetic moment of Mn2+ ions in ZnO:Mn (2 at%.) nanocrystals obtained by ultrasonic pyrolysis of aerosol which are responsible for their ferromagnetic properties is given. In order to investigate the influence of structural defects on the value of magnetic moment the samples were heat treated in air. The calculation was performed on the basis of the analysis of magnetization curves and EPR spectra. It was shown that the defective state of ZnO:Mn nanocrystals has a significant effect on the magnetic moment. The values of magnetic moment for the synthesized sample significantly exceed the values of magnetic moment compared to similar nanocrystals obtained by other methods. The assumption is made that this result is due to the presence of an additional component in the magnetization of the defective samples. In addition to the paramagnetism of Mn2+ ions, there may be the paramagnetism of the defective shell of ZnO:Mn nanocrystals. After the elimination of structural defects by heat treatment of samples in air and in a gas mixture with hydrogen, the magnetic moment for Mn2+ ions, which form the ferromagnetic properties of nanocrystals, was determined. The value of this magnetic moment is 0.02µB, where µB is the Bohr mangiton. Such ions, according to the model of bound magnetic polarons, are part of ferromagnetic clusters and take part in the formation of the ferromagnetic properties of the samples. Keywords: magnetic moment, nanocrystals, ultrasonic aerosol pyrolysis, heat treatment, hydrogen.

This study presents an unmanned aerial vehicle (UAV)-borne vector magnetometer (MAG) system and proposes a new data-processing technique for modeling the residual magnetic anomalies of three types of landmines: the metallic antitank M15, the metallic antipersonnel M16, and the minimum-metal antitank M19. The burial depth and magnetic moment of these landmines were estimated using the measured and simulated residual magnetic anomalies based on the proposed UAV-borne vector MAG model. Initial in-flight validation showed a strong correlation between the residual magnetic anomaly maps obtained from measurements and simulations. To verify the detection capability in real-world conditions, the UAV-borne MAG system was tested at the Korean Combat Training Center. Both simulations and experiments demonstrated the effectiveness of the proposed data-processing method and UAV-borne MAG model in accurately modeling the residual magnetic anomalies of landmines with metallic components. This approach will facilitate the automated detection of M15, M16, and M19 landmines with high detection rates and enable accurate classification.

Monovalent thulium iodide TmI, formed by the reaction of thulium with iodine at 680°C, does not dissolve in isopropylamine (IPA), but quickly disproportionates to form finely dispersed thulium metal and TmI2(IPA)2. Similar transformations are observed in dimethoxyethane, but disproportionation proceeds significantly slower. It is impossible to isolate the powdered thulium formed in this case. The observed transformations are the first example of disproportionation of a monovalent lanthanide salt. [ABSTRACT FROM AUTHOR]

Herein, a comprehensive theoretical analysis of Tm‐based chalcogenides MgTm2Y4 (Y = S, Se) is performed to understand magnetic, optical, mechanical, and transport characteristics. And, Perdew–Burke–Ernzerhof generalized gradient approximation (PBEsol‐GGA) functional and modified Becke–Johnson (mBJ) potentials are employed while computing the mechanical and spin‐polarized electronic properties, respectively. The structural stability of both spinels is confirmed using formation energy and Born stability criteria. Both spinels are found exhibiting ductile nature according to the computed Pugh's and Poisson's ratios. For observing the room‐temperature ferromagnetism, Curie temperature is calculated. Furthermore, spin‐polarized electronic properties reveal that both spinels exhibit ferromagnetic nature, which is induced due to coupling among Tm‐ and S/Se‐related constituent states. The potential optoelectronic applications are suggested by computing and discussing dielectric constant, refractive index, and absorption coefficient. BoltzTraP code is used to investigate the thermoelectric features of MgTm2Y4 (Y = S, Se) in the 200–800 K temperature range. [ABSTRACT FROM AUTHOR]

Growth pattern and electronic and magnetic properties of AgnCr (n = 1–16) clusters have been investigated via density functional theory (DFT) combined with CALYPSO structure search method. The optimized geometry shows that the growth of the global minimum structures of AgnCr clusters have obvious rule. when n > 12, silver atoms grow around an icosahedron which is almost unchanged in each structure. Analyses of electronic properties indicate that the doped Cr atom can only enhance the stability of larger silver clusters. Optical absorption and photoelectron spectra of AgnCr isomers have been predicted and can be used for their structural identification. The icosahedral Ag12Cr cluster with large energy level gap can be seen as a superatom. The adsorption capacity of Cr atom in AgnCr cluster to CO is much higher than that of free Cr atom. The intensity of IR and Ramam spectra can be dramatically enhanced when CO is absorbed on AgnCr cluster that Cr atom is encapsulated by Ag atoms. Moreover, the red shift of IR and Raman spectra of CO adsorbed on these clusters is also very small compared to free CO. Magnetism calculations show that the magnetic moment of AgnCr clusters decreases linearly from n = 6 to 12 and increases linearly from n = 12 to 16. The total magnetic moment of AgnCr cluster is mainly localized on the Cr atom. The change of magnetic moment of Cr atom is related to the charge transfer between Cr and Ag atoms. [ABSTRACT FROM AUTHOR]

The growth law, electronic properties and spectra of Fenλ (n = 2–18; λ = 0, ±1) clusters have been examined by density functional theory (DFT) and an unbiased structure prediction method. Extensive geometry optimizations have been executed and show that the global minimum structures of Fenλ clusters have a distinct growth law when n is 8–18. For n = 8–13 and 14–18, the iron atoms grow around a decahedral and icosahedral iron cluster core, respectively. Based on the present ground states, the calculated electronic parameters are in line with the experimental values. The thermal stability of charged iron cluster is higher than that of neutral iron cluster. The octahedral and icosahedral clusters are more stable than their neighbors. The former has low chemical activity and may be a superatom. The magnetic moment of Fe atom weakens in the cluster. The UV spectra, photoelectron spectra (PES) and infrared and Raman spectra of the Fenλ clusters have been predicted and the global minimum structures of the Fen− clusters are determined by comparing the theoretical PES with the experimental results. [ABSTRACT FROM AUTHOR]

Cobalt-substituted magnetite CoxFe3-xO4 nanoparticles were synthesized using a sol-gel auto-combustion method using citric acid as a fuel. The samples were characterized by X-ray diffraction (XRD), fieldemission scanning electron microscopy (FESEM), Fourier transform infrared (FTIR) spectroscopy, optical ultraviolet-visible (UV-Vis) spectroscopy, and vibrating sample magnetometer (VSM). XRD studies revealed cobalt replacing iron, forming a single phase with a crystalline size of 17-25 nm. FESEM and FTIR spectra showed a metal-oxygen bond, while UV-Vis spectra showed absorbance spectra and Kubelka-Munk theory. Magnetic properties were studied using VSM, revealing increased saturation magnetization and a constant squareness ratio, confirming the single domain of cobalt-doped Fe3O4 nanoparticles. These nanoparticles have potential applications in spintronics, nanoscale devices, and supercapacitors. [ABSTRACT FROM AUTHOR]

In this work, we studied the reaction mechanisms for CO2 reduction reaction (CRR) on the iron‐doped graphene and its coordinating sulfur (S) and nitrogen (N) variants, FeNnS4‐n (n=1–4), using density functional theory calculations. Our results revealed that the electronic property and catalytic reactivity of the surfaces can be tuned by varying the N and S atoms ratio. The CRR activities of the mixed surfaces, FeN3S1, FeN2S2, and FeN1S3, were better than FeN4 and FeS4, where the absolute value of the limiting potential of the mixed surface decreased by 0.3 V. Considering the stability, we suggest FeN3S surface to be favorable for CRR. For the bare surfaces, we found a positive linear correlation between the magnetic moment and the charge of Fe metal. For these surfaces, the reduction of CO (*CO+(H++e−)→*CHO) was important in deciding the limiting potential. We found that the adsorption energy of CO displayed a volcano relationship with the magnetic moment of the Fe atom. The study showed that the change of local coordinating structure around the Fe atom could modify the electronic and magnetic properties of the active Fe center and improve the CRR activity performance. [ABSTRACT FROM AUTHOR]

The structural, electronic, mechanical and magnetic properties were investigated for Cr2LuSn1−xPbx quaternary Heusler compounds by employing first-principles calculations framed fundamentally within density functional theory. The exchange–correlation potential is evaluated using the generalized gradient approximation (GGA)within the Perdew–Burke–Ernzerhof parameterization. We optimized our structure, and the most stable crystal structure is AlCu2Mnl-type, and at equilibrium, equilibrium lattice parameters have been determined. The calculated lattice constants for Cr2LuSn and Cr2LuPb are 6.5906 Å and 6.6769 Å, respectively. The electronic structures show that both compounds have half-metallic properties by showing 100% spin polarization near the Fermi level. The electronic band structures and density of states of our compounds show a half metallic character with total magnetic moments, 5.00 μ b per formula unit with indirect band gap, 0.527 eV and 0.300 eV for Cr2LuSn and Cr2LuPb, respectively. The mechanical stability reveals that all our compounds are stable mechanically. The Young's modulus, Poisson's ratio, anisotropy factor Zener and density were calculated and discussed in detail. Furthermore, the temperature and pressure effect on bulk modulus, Debye temperature and heat capacity at constant volume and constant pressure C v , , respectively, have been investigated by the quasi-harmonic Debye model. These alloys seem to be a potential candidate of spintronic devices. [ABSTRACT FROM AUTHOR]

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In this paper, we study the orientational texturing and static magnetization of a small multi-core particle (MCP) that includes a few immobilized superparamagnetic particles (SPPs). We focus on the consideration of the MCPs containing 7 and 8 SPPs, which are located randomly or at the nodes of a simple cubic lattice. The results are obtained using Monte Carlo computer simulations. It is shown that intensive dipole–dipole interaction leads to the formation of an orientational texturing of the SPP's magnetic moments, which strongly depends on the location of the SPPs inside the MCP. The magnetization laws of MCPs are compared with the continuous medium magnetostatics. For strongly interacting SPPs there is a big difference between the simulation results for the magnetization of the MCPs with cubic structure and the magnetization of continuous system of SPPs located in simple cubic lattice. The magnetization of the MCP for each specific random location of the SPPs also differs from the magnetization of continuous media of SPP gas, however, the average value of the MCP magnetization coincides with the continuous media magnetostatics. [ABSTRACT FROM AUTHOR]

This paper contains data and results from Density Functional Theory (DFT) investigation of 423 distinct X2YZ ternary full Heusler alloys, where X and Y represent elements from the D-block of the periodic table and Z signifies element from main group. The study encompasses both “regular” and “inverse” Heusler phases of these alloys for a total of 846 potential materials. For each specific alloy and each phase, a range of information is provided including total energy, formation energy, lattice constant, total and site-specific magnetic moments, spin polarization as well as total and projected density of electronic states. The aim of creating this dataset is to provide fundamental theoretical insights into ternary X2YZ Heusler alloys for further theoretical and experimental analysis.