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A tremendous amount of research has witnessed the exploration of two-dimensional (2D) materials with intrinsic ferromagnetism and diverse physical properties. However, the low Curie temperature and deficient magnetic anisotropy hinder their practical applications in nanoscale spintronics. Based on first-principles calculations, we propose a new family of 2D ternary transition metal tellurides, CrX2Te4 (X = Al, Ga, and In), with both structural and magnetic stabilities at room temperature. Our calculations demonstrate that the 2D CrX2Te4 crystal exhibits the intrinsic 100% spin-polarized half-metallic feature with spin-up metallic and spin-down semi-conducting properties. With the remarkable magnetic moment of 4 μB per Cr atom, both 2D CrAl2Te4 and CrGa2Te4 crystals perform robust ferromagnetism with the out-of-plane magnetic anisotropy, while the 2D CrIn2Te4 crystal prefers the in-plane easy magnetization axis. The Monte Carlo simulation based on the 2D Heisenberg model shows that the critical Curie temperatures of the 2D CrAl2Te4, CrGa2Te4, and CrIn2Te4 crystals could reach 466, 431, and 536 K, respectively. Moreover, the magnetic exchange strength and magnetic anisotropy could be further enhanced by the in-plane biaxial strain. The novel electronic and magnetic features promote 2D CrX2Te4 (X = Al, Ga, and In) crystals as a new family of two-dimensional intrinsic ferromagnetic materials for next-generation advanced spintronics. [ABSTRACT FROM AUTHOR]

We calculated the structural, electronic, mechanical and thermoelectric properties of the iridium-based, newly proposed Heusler alloys Ir2V (In, Sn). Both alloys have an indirect bandgap at the Fermi level in the spin-down channel, with metallic overlap in the spin-up channel, indicating the presence of half-metallic behavior. The Hubbard interactions contribute to the half-metallic behavior of these alloys. The magnetic moments are estimated using the Slater–Pauling formula, indicating large values of magnetic moments in all alloys with predominant contribution from the V atom. The stability of these alloys is established by their phonon frequencies, as well as formation and cohesive energies. Elastic constants such as Poisson's ratio, Pugh's ratio and various types of moduli affirm their mechanical stability and strength. Further, the effect of temperature on spin transport is also reported. These materials are prospective candidates for high-temperature thermoelectric applications, according to an analysis of high Curie temperatures and various transport coefficients. [ABSTRACT FROM AUTHOR]

Heusler alloy has been widely utilized in magnetoresistive sensors to enhance the device performance. In this work, we theoretically investigate the performance of Heusler-alloy-based magnetoresistive sensors with a synthetic antiferromagnet (SAF) layer. The atomistic model combined with the spin accumulation model will be used in this work. The former is used to construct the reader stack and investigate the magnetization dynamics in the system. The latter is employed to describe the spin transport behavior at any position of the structure. We first perform simulations of the exchange bias (EB) phenomenon in the IrMn/ C o 2 F e S i (CFS) system providing a high EB field. Then, a realistic reader stack of IrMn/CFS/Ru/CFS/Ag/CFS is constructed via an atomistic model. Subsequently, the resistance–area product (RA) and magnetoresistance (MR) ratio of the reader can be calculated by using the spin accumulation model. As a result of the spin transport behavior in the Heusler-alloy-based reader stack including SAF structure at 0 K, an enhancement of the MR ratio up to 120 % and RA < 40 m Ω ⋅ μ m 2 can be observed. This study demonstrates the important role of the Heusler alloy and SAF layer in the development of magnetoresistive sensors for the application of readers in hard disk drives with an areal density beyond 2 Tb in−2. [ABSTRACT FROM AUTHOR]

Half Heusler materials exhibit excellent thermoelectric and mechanical properties, rendering them potential candidates for advanced thermoelectric devices. Currently, the developments on interrelated devices are impeded by their inherent brittleness and limited ductility. Nevertheless, it exists the potential ductility on half Heusler materials with face-centered cubic sub-lattices through the expectation of the occurrence of shear-induced 'catching bonds' which can result in excellent ductility on other face-centered cubic materials. This work focuses on half Heusler thermoelectric materials XFeSb (X = Nb, Ta) and SnNiY (Y = Ti, Zr, Hf), the shear deformation failure processes are deeply investigated through the first principle calculations. Shear-induced 'catching bonds' are found on XFeSb (X = Nb, Ta) along the (111)/<-1-12> slip system, which releases the internal stress and exactly resulting in the potential ductility. According to the thermodynamic criterion based on generalized stacking fault energy, the essence of shear-induced 'catching bonds' are interpreted as the (111)/<-110> slips formed by several 1/3(111)/<-1-12> partial dislocations motions. During the (111)/<-1-12> shear on SnNiY (Y = Ti, Zr, Hf), the structural integrity is maintained without inducing 'catching bonds'. Different deformation processes occurring in the identical crystal structure are elucidated through the energy explanation, revealing that shear-induced 'catching bonds' originate from the crystal plane cleavage on the (111) plane. The present works offer significant advantages for the assessment and comprehension of shear-induced 'catching bonds' in other materials and facilitate the development of XFeSb (X = Nb, Ta)-based thermoelectric devices with excellent ductility. [ABSTRACT FROM AUTHOR]

Two-dimensional transition metal borocarbides with intrinsic magnetism have garnered significant research attention due to their potential applications in spintronics. Using density functional theory calculations, we designed a type of transition metal borocarbides with two distinct configurations, TMBC-Is and TMBC-IIs (TM = V–Co), and explored their electronic and magnetic properties. Our results demonstrate that all the studied systems exhibit both thermal and kinetic stability. Notably, four systems of MnBC-I/MnBC-II and FeBC-I/FeBC-II are robust ferromagnetic (FM) half metals (HMs) with Curie temperatures of 145, 180, 108, and 315 K. Expect FeBC-II monolayer, FM to antiferromagnetic transition occurs for three other FM HMs under 8%–10% compressive strains, while FM HM to FM semiconductor transition is found for MnBC-II monolayer under 8% tensile strain. These findings provide a promising way to design two-dimensional FM HMs, which hold potential applications in spintronics. [ABSTRACT FROM AUTHOR]

Magnetic properties of 3d transition metal ion doped methylammonium lead chloride (MAPbCl3) have been studied by ab-initio calculations in the framework of density functional theory. The study of spin–spin interactions reveals that doping (about 2%) of Ti, V, Cr, Mn and Fe at the Pb site of MAPbCl3 shows stable ferromagnetic ordering along with the half-metallic behaviour. 3d orbital electrons of the dopants are primarily responsible for the origin of the magnetic moment and the remaining part comes from the p-d exchange interaction between the 3d orbital electrons of the dopants and the 6p orbital electrons of Pb in the vicinity of the doping position. Additionally, the band structure calculations suggest that the doped system shows n/p-type semiconducting behaviour. Ferromagnetism, along with semiconducting behaviour in transition metal ion-doped MAPbCl3, will be suitable for spintronic applications. [ABSTRACT FROM AUTHOR]

Half-metallic ferromagnetic Heusler alloys attracted much attention in the last few decades due to their significant physical properties as well as its potential applications in spintronic devices. To explore and predict the various physical properties of Co-based Heusler alloy, Co2MnSi (CMS), First principles calculations are of interest and has been used in the present study. Optimized E–V curves represent that CMS alloy is most stable in its magnetic L21 structural phase. The electronic charge density plot represents the ionic bonding along with co-valent character for the compound. DOS and BS calculations shows 100% spin polarization at Fermi level (EF) which confirms the half metallic character of the compound. DOS exhibited the prominent role of Co-3d and Mn-3d electronic states along with Si-2p electronic states. Estimated magnetic moment of Co2MnSi Heusler alloy was found to be ~ 5μB per f. u. which is in line with the Slater-Pauling behaviour. Dynamical stability of Co2MnSi Heusler alloy has also been verified by the phonon dispersion curves which revealed that compound is dynamically stable. Additionally, the physical properties have also been explored as a consequence of SOC and significant changes in electronic and optical properties were observed. The observed significant results of electronic, magnetic, and optical properties of CMS Heusler alloy makes it promising towards potential application in optical and spintronic devices. [ABSTRACT FROM AUTHOR]

The electronic and magnetic features are investigated for doped diluted magnetic semiconductor, specifically magnesium selenide (MgSe). The semiconductor is doped with a single impurity of either zirconium (Zr) or niobium (Nb). To conduct this investigation, a combination of the Korringa-Kohn-Rostoker coherent potential approximation, generalized gradient approximation (GGA) first-principles calculation, and the parametrization method of Pedrew Burke and Ernzerhof (PBE) is used. Our results show that the incorporation of Zr and Nb into the host composite makes a significant contribution to the total magnetic moment of the doped system. The total magnetic moment for M g 1 - x D x S e (D= Nb,Zr) is - 0.58 μ B and - 0.38 μ B for Nb and Zr, respectively, induced by the polarization of the spin at Fermi level ( E F ). Moreover, the ferromagnetic state is stable due to the double exchange mechanism and exhibits a remarkable Curie temperature (Tc) with maximum values of 940 K and 619 K for 2% concentration of Nb and 20% of Zr, respectively. This result leads to interesting magnetic behavior. On the other hand, the double exchange, responsible for short-range interactions mediated by Selenium atoms, arises from the occurrence of p-d orbital hybridization. As a consequence, doping MgSe with Zr and Nb transition metals opens the door to explore and develop new devices in spintronic areas, under room temperature. [ABSTRACT FROM AUTHOR]

In the search for new and novel materials for various thermo‐physical applications, we have reported the magnetic, electronic, mechanical, thermal, and thermoelectric transport properties of two full Heusler alloys (HAs), Ru2MnV and Ru2MnNb. In order to obtain a stable structure, volume optimization was carried out in the Fm‐3m (225) and F43‐m (216) space groups. The Fm‐3m space group was found to be a stable phase for both alloys. Electronic results show the metallic nature of these alloys. Ferromagnetic moments of 4.06 and 4.18 μB were obtained for Ru2MnV and Ru2MnNb, respectively. Mechanical results show a brittle nature for Ru2MnV and a ductile nature for Ru2MnNb with a high melting temperature for Ru2MnV. Thermoelectric properties such as figure of merit along with Seebeck coefficient, electrical conductivity, power factor, and thermal conductivity have also been calculated. Furthermore, the thermodynamic results of the studied materials have also been evaluated to understand the nature of various thermodynamic parameters with respect to temperature and pressure. [ABSTRACT FROM AUTHOR]

This document is a summary of a special issue of the journal Crystals, which focuses on crystalline materials and their properties. The articles cover a wide range of topics including composition selection, processing conditions, synthesis, characterization, and applications studies. The materials studied include Heusler alloys, tungsten-based materials, copper-tin alloys, manganese-nickel alloys, and gallium-based magnetic semiconductors. The articles also explore properties such as elasticity, conductivity, magnetism, and optical behavior. Specific applications discussed include dye degradation and antimicrobial, antioxidant, and anticancer activity. The last article in the special issue discusses the production of nickel-zinc ferrites using the sol-gel method and explores their magnetic behavior. The editors express their gratitude to all the contributors and reviewers for their help in improving the quality of the manuscripts. [Extracted from the article]

Rare-earth (RE) doping has been demonstrated as a feasible approach to improve the cyclic performance of Ni-Mn-based Heusler alloys, but the current demonstration of underlying mechanism is simply ascribed to strengthening of the grain boundary cohesion. In this work, the effects brought by RE doping on microstructure, stress induced martensitic transformation behavior and cyclic stability of Ni-Mn-based alloys were systematically investigated. By Tb doping, a stable adiabatic temperature change (|ΔTad|) of ∼ 5.5 K over 1000 cycles with no significant degradation was obtained in (Ni43Mn47Sn10)99.5Tb0.5. (1) Through the in-situ digital image correlation strain measurement and in-situ SEM observation upon loading process, it revealed a multipoint nucleation of the martensitic transformation across the specimen arising from the intergranular NiSnTb secondary phase as nucleate sites, which weakens the strain concentration and suppresses the crack tendency. (2) The multipoint nucleation promotes the transformation volume fraction, making the large |ΔTad| could be driven by a small transformation strain (Δεtr) and (Ni43Mn47Sn10)99.5Tb0.5 yields a |ΔTad/Δεtr| up to 8.7 K %−1. Such reduction in applied strain further alleviates the extension of the cracks. Both the two factors brought by Tb doping in (Ni43Mn47Sn10)99.5Tb0.5 give rise to the enhancement in cyclic stability of the large elastocaloric effect.

Chemical ordering in NiMn-based Heusler alloys with magnetostructural phase transition is crucial for understanding the physics of the phase transition. In the new field of all-d-metal Ni(Co)MnTi Heusler alloys, the experimental determination of chemical order is challenging due to the low difference in scattering power of the different elements. Here, we report a combined approach of neutron and x-ray diffraction for an analysis of chemical order in Ni(Co)MnTi alloys and show that no Heusler-typical L 2 1 order between Ti and Mn is present. Furthermore, Co and Ni atoms do not exhibit order among them; however, the phase transition of Co containing samples can be shifted significantly by changing the degree of B 2 order with proper heat treatment. Using first-principles calculations, we reveal how the structural and magnetic sub-systems depend on the degree of B 2 disorder. [ABSTRACT FROM AUTHOR]

The structure and magnetic properties of epitaxial Heusler alloy films (Co2FeGe) deposited on MgO (100) substrates were investigated. Films of 60 nm thickness were prepared by magnetron co-sputtering at different substrate temperatures (TS), and those deposited at room temperature were later annealed at various temperatures (Ta). X-ray diffraction confirmed (001) [110] Co2FeGe || (001) [100] MgO epitaxial growth. A slight tetragonal distortion of the film cubic structure was found in all samples due to the tensile stress induced by the mismatch of the lattice parameters between Co2FeGe and the substrate. Improved quality of epitaxy and the formation of an atomically ordered L21 structure were observed for films processed at elevated temperatures. The values of magnetization increased with increasing TS and Ta. Ferromagnetic resonance (FMR) studies revealed 45° in-plane rotation of the easy anisotropy axis direction depending on the degree of the tetragonal distortion. The film annealed at Ta = 573 K possesses the minimal FMR linewidth and magnetic damping, while both these parameters increase for another TS and Ta. Overall, this study underscores the crucial role of thermal treatment in optimizing the magnetic properties of Co2FeGe films for potential spintronic and magnonic applications.

Density functional theory (DFT)-based calculations were used to calculate the physical properties of the full Heusler compound Pd2MnSb. The WIEN2K code is used with various approximations, such as generalized Gradient approximation (GGA) and (GGA + U) potentials, to investigate the structural, electronic, and magnetic responses. The unit volume cell is optimized to achieve the ground state energy level. The calculated band structure with both potentials confirms the metallic behavior of the selected compound, Pd2MnSb. The total density of states is also calculated by using these potentials, which confirms their metallic behavior. The calculated partial density of state with GGA and GGA + U potentials confirmed the particular contribution of atoms. We have calculated the magnetic properties with the GGA and GGA + U potentials to find out the total magnetic moment values that are suitable with the available experimental data. The calculated magnetic moments show that Pd2MnSb is a magnetized material. These investigated properties show that Pd2MnSb has metallic magnetized characteristics and is perfectly suitable for the applications of mass storage devices as a ferromagnetic material. [ABSTRACT FROM AUTHOR]

The primary objective of this study is to investigate the influence of spin-orbit coupling and atom type on the electronic, optical, and thermoelectric properties of LuXNi2Sn2 (X = V, Nb, and Ta) double-half Heusler alloys. To achieve this, calculations were performed using the full potential linearized augmented plane wave method within the framework of density functional theory. Both full relativistic and scalar relativistic calculations were employed. The exchange-correlation interactions in this study were modeled using the PBEsol version of the generalized gradient approximation when calculating the structural ground state parameters. For the analysis of electronic, optical, and thermoelectric properties, the modified Becke–Johnson potential was employed. The modified Becke–Johnson potential was specifically chosen for its capability to improve the description of band gaps, particularly for systems with small band gaps, such as the LuXNi2Sn2 (X = V, Nb, and Ta) double-half Heusler materials examined in this study. This potential offers a more accurate representation of the electronic properties, enabling a more reliable analysis of the optical and thermoelectric characteristics of the materials under investigation. The examined LuXNi2Sn2 (X = V, Nb, and Ta) materials exhibit semiconductor behaviour, with band gaps smaller than 0.4 eV that can be controlled by varying the "X" atom. The charge carriers, specifically holes and electrons, exhibit light effective masses, indicating high mobility. Furthermore, these compounds exhibit low thermal expansion coefficients and satisfy the criteria for thermodynamic stability. In terms of optical properties, they display substantial absorption coefficients in the ultraviolet (UV) light region, high optical conductivity, and high reflectivity in the visible light region. Considering their favourable power factor and figure of merit characteristics, the LuXNi2Sn2 (X = V, Nb, and Ta) materials possess the potential to be promising candidates for thermoelectric applications. [ABSTRACT FROM AUTHOR]

Double perovskites such as Sr2CrReO6 attract great scientific attention owing to their high Curie temperatures (TC ≥ 550 K) as well as large magnetoresistances. However, both the specific physical mechanism of high TC and magnetic ground state in Sr2CrReO6 remain ill‐defined. In order to clarify and understand these issues, we studied its critical phase transition characteristics using critical behavior analysis. We found that the obtained critical exponents (β = 1.115 and γ = 2.224) are quite different from any traditional universality class. The abnormal critical behavior implies that at the quantum critical point, Sr2CrReO6 exists a strong competition among several magnetic interactions. By analyzing their effective critical exponents, we show that the double perovskite Sr2CrReO6 is really an ordered and homogeneous ferromagnet. With the help of Takahashi's theory, the nature of ferromagnetism in Sr2CrReO6 is confirmed to be localized instead of itinerant. The results of this research will provide new insights into the origins of high TC as well as the magnetic ground state in this double perovskite. [ABSTRACT FROM AUTHOR]

Information on the energy, charge, and spin characteristics of Pd1-xMexMnSn alloys (Me = Co, Ni, x = 0.0--1.0) is obtained using band calculations within the FLAPW (full-potential linearized augmented-plane-wave) model. As determined, an increase in the concentration of the cobalt or nickel atoms leads to an increase in the interatomic electron density inside the alloys. This results in both a concurrent reduction in the parameters of their crystal lattices and an increase in the binding energies of the atoms. The number of electrons Q within the atomic spheres of Pd, Mn, and Sn in cobalt-containing alloys exceeds the corresponding values for nickel-containing phases, and the dependences of Q exhibit a systematic tendency to increase with the growth of substitutional- atoms' concentrations. The observed polarization of valence electrons leads to the appearance of magnetic moments on the atoms of the alloys. The magnetic moments of metal atoms are ferromagnetically ordered, and their magnitude depends on the type and concentration of substitutional atoms. [ABSTRACT FROM AUTHOR]

Double perovskites such as Sr2CrReO6 attract great scientific attention owing to their high Curie temperatures (TC ≥ 550 K) as well as large magnetoresistances. However, both the specific physical mechanism of high TC and magnetic ground state in Sr2CrReO6 remain ill‐defined. In order to clarify and understand these issues, we studied its critical phase transition characteristics using critical behavior analysis. We found that the obtained critical exponents (β = 1.115 and γ = 2.224) are quite different from any traditional universality class. The abnormal critical behavior implies that at the quantum critical point, Sr2CrReO6 exists a strong competition among several magnetic interactions. By analyzing their effective critical exponents, we show that the double perovskite Sr2CrReO6 is really an ordered and homogeneous ferromagnet. With the help of Takahashi's theory, the nature of ferromagnetism in Sr2CrReO6 is confirmed to be localized instead of itinerant. The results of this research will provide new insights into the origins of high TC as well as the magnetic ground state in this double perovskite. [ABSTRACT FROM AUTHOR]

The magnetic field-sensitivity of martensitic phase transitions (MPTs) responsible for magnetocaloric effects has been examined in B-substituted Ni50Mn34.8In15.2−xBx Heusler alloys (x = 1, 2, 3, and 4). Increasing boron substitution acts as a positive chemical pressure similar to the effect of hydrostatic pressure (p) and shifts the martensitic phase transition temperature (TM) toward higher temperature. The observed structural compatibility of the MPT results in a lower thermal hysteresis (ΔThyst<5 K at low field). ΔThyst remains almost unchanged; however, the field sensitivity of TM decreases significantly with increasing B content or application of p. As a result, the reversibility of the isothermal entropy change (|ΔSrev|) reduces for higher B concentration or under hydrostatic pressure p. The experimental observation reveals that the lower field-sensitivity of the MPT with increasing B or p is associated with the simultaneous increase in the magnetocrystalline anisotropy energy (MAE) and decrease in the Zeeman energy (ZE). The relatively larger ZE and smaller MAE for x = 1 result in the improved reversibility of the entropy change (|ΔSrev| = 21.48 J/kg K for Δμ0H = 5 T), which is comparable to or even larger than the values reported for similar Heusler alloys. [ABSTRACT FROM AUTHOR]

The DFT method investigated the total and partial magnetic moments, half-metallic characters, and pressure-dependent elastic properties of Zr2RhTl alloy. According to the ground state properties, the FM phase is more stable in energy than the AFM and NM phases. The Curie temperature value was obtained as 897.43 K with the help of the energy differences of the AFM and FM phases. The total magnetic moment of Zr2RhTl alloy was obtained as 2.00 µB/f.u. Partial magnetic moment values were obtained as 0.810, 0.506, 0.032, and 0.009 µB for Zr1, Zr2, Rh, and Tl atoms, respectively. All these total and partial magnetic moment values and Curie temperatures were supported by the Effective Field Theory (EFT) method. In addition, partial Curie temperatures of Zr2RhTl alloy were calculated by EFT separately for each element. The up-spins of Zr2RhTl alloy show metallic character in both the GGA and GGA + mBJ approximations, while the down-spins have band gaps of 0.698 and 0.699 eV, respectively. Electronic properties were also supported by GGA + U (U = 1, 2, 3 eV) interactions. Therefore, Zr2RhTl alloy is a true half-metallic ferromagnetic material. Zr2RhTl alloy was elastically stable, and the Debye temperature was calculated as 221.496 K at 0 GPa. All calculations obtained using two different methods (DFT and EFT) and two different approximations (GGA and GGA + mBJ) support each other. Therefore, Zr2RhTl alloy proved to be a very suitable material to be used as an alternative for spintronics. [ABSTRACT FROM AUTHOR]

In the article, within the framework of the theory of micromagnetism, a magneto-elastic microstructural model of the behavior of a ferromagnetic material with the shape memory (Heusler alloy) in a magnetic field is constructed. The dynamics of the magnetic process is described by the Landau-Lifshitz-Gilbert equation. Using the Galerkin procedure, variational equations corresponding to the differential relations of the magnetic problem are written out. A martensitic structure of the type "herringbone" (a twinned variant of martensite) with magnetic domains located at an angle of 180 ° is considered. 90-degree magnetic domain walls are the boundaries of the twins. The finite element method models the formation of these walls and the distribution of the magnetization vector in them. The evolution of this magnetic structure is investigated, namely the movement and interaction of 180-degree magnetic domain walls when an external magnetic field is applied in various directions. The problems of the formation of twins from the martensite variants (the twinning problem) and their disappearance (the detwinning problem) in an external magnetic field are considered. On the plane separating the two variants of martensite, the Hadamard compatibility condition (or twinning equation) is written out. The solution of this equation is given and the processes, that this equation describes, are considered in detail. The detwinning condition for a ferroalloy with the shape memory in a magnetic field is proposed and the processes related to the reorientation (detwinning) of the martensitic variants forming a twin are discussed. The problems considered earlier without taking into account the detwinning process are supplemented by this process, the magnetization curves are constructed and the components of the strain tensor are determined. The results obtained are in good agreement with the known experimental data. [ABSTRACT FROM AUTHOR]

In this article, the downsizing of functional Heusler alloys is discussed, focusing on the published results dealing with Heusler alloy nanowires. The theoretical information inspired the fabrication of novel nanowires that are presented in the results section of the article. Three novel nanowires were fabricated with the compositions of Ni66Fe21Ga13, Ni58Fe28In14, and Ni50Fe31Sn19. The Ni66Fe21Ga13 nanowires were fabricated, aiming to improve the stoichiometry of previous functional Ni-Fe-Ga Heusler nanomaterials with a functional behavior above room temperature. They exhibit a phase transition at the temperature of ≈375 K, which results in a magnetocaloric response of |ΔSM| ≈ 0.12 J·kg−1·K−1 at the magnetic field change of only μ0ΔH = 1 T. Novel Heusler alloy Ni58Fe28In14 nanowires, as well as Ni50Fe31Sn19 nanowires, are analyzed for the first time, and their magnetic properties are discussed, introducing a simple electrochemical approach for the fabrication of nanodimensional alloys from mutually immiscible metals. [ABSTRACT FROM AUTHOR]

We synthesize CoFeRuSn equiatomic quaternary Heusler alloy using arc-melt technique and investigate its structural, magnetic, and transport properties. The room temperature powder x-ray diffraction analysis reveals that CoFeRuSn crystallizes in cubic crystal structure with small amount of DO3-disorder. The field dependence of magnetization shows non-zero but small hysteresis and saturation behavior up to room temperature, indicating soft ferromagnetic nature of CoFeRuSn. The magnetic moment estimated from the magnetization data is found to be 4.15 μB/f.u., which is slightly less than the expected Slater–Pauling rule. The deviation in the value of experimentally observed moment from the theoretical value might be due to small disorder in the crystal. The low temperature fit to electrical resistivity data shows the absence of quadratic temperature dependence of resistivity, suggesting half-metallic behavior of CoFeRuSn. The high Curie temperature and possible half-metallic behavior of CoFeRuSn make it a highly promising candidate for room temperature spintronic applications. [ABSTRACT FROM AUTHOR]

This paper will focus on the comparative study of the structural, electronic, magnetic, optical, and thermoelectric properties of the two Heusler systems Ag2TiGa and Ag2VGa in the inverse L21 Hg2CuTi structure. Using the density functional theory‐based wien2k code, which implements the computational methods used in this study, namely GGA, GGA‐mBJ, GGA + U, and GGA + SOC (spin‐orbit coupling). The band structures show that all two structures studied are metallic. The spin density of states of Ag2VGa has evident spin splitting near the Fermi level, and the total magnetic moment of the Ag2VGa structure is 2.19 μB, which indicates that Ag2VGa is magnetic. The full‐Heusler Ag2VGa material can be used as spintronic materials due to their high spin polarization (about 50%). While Ag2TiGa has low polarization so it is bad electronically, but better thermoelectrically than Ag2VGa. So, the full‐Heusler Ag2TiGa material may also be considered as a potential candidate for thermoelectric applications at room temperature. Studies of the two new Heusler alloys may provide a theoretical reference for subsequent theoretical research and experimental synthesis of Ag‐based Heusler alloys. [ABSTRACT FROM AUTHOR]

This article is about the study of structural, elastic, mechanical, electronic, and magnetic properties of two variant perovskites In2NbX6 (X = Cl, Br) using density functional theory. To the best of our information all calculations were carried out for the first time. The results established the cubic state stability of the present compounds in the FM phase. The thermodynamic and perovskites phase stabilities are respectively confirmed from negative values of formation energies and tolerance factor. The calculated elastic constants C11, C12, and C44 confirmed the mechanical stability of In2NbX6 compounds. The mechanical properties confirmed ductile nature of In2NbCl6 and brittle nature of In2NbBr6. The electronic properties showed that these compounds were metallic in spin up state and semiconductor in spin down state. The magnetic moments were calculated as 1 μB for both the compounds majorly associated with the Nb atom. The spin dependent electrical conductivity was calculated via BoltzTrap code. Besides half metallic nature, high spin dependent electrical conductivities reveals that In2NbX6 variant perovskites compounds are suitable for spintronic applications. [ABSTRACT FROM AUTHOR]

N‐type ZrNiSn‐based alloys reach a record thermoelectric figure of merit zT ≈1.2 by increasing the carrier concentration to 4–5 × 1020 cm−3. In this work, It is reported that a comparable zT can also be realized in trace Ru‐doped ZrNiSn‐based alloy at even lower temperature by decreasing the carrier concentration. Compared to the previously reported Co doping, the doping of Ru results in a more effective reduction in carrier concentration, and thus higher Seebeck coefficient, lower electronic thermal conductivity, and enhanced thermoelectric performance. The electronic specific heat coefficient of the ZrNi1‐xRuxSn sample remains constant with increasing Ru content, indicating no obvious change in the density of states effective mass. Theoretical calculations show that the doping of Ru has negligible effect on the bottom of conduction band. The lattice thermal conductivity is further reduced by alloying Ti and Hf at the Zr site, and the bipolar diffusion is suppressed by doping of 0.5 at.% Sb. As a result, Ti0.25Zr0.5Hf0.25Ni0.99Ru0.01Sn0.995Sb0.005 reaches not only a zT value of 1.1 at 773 K but also a record average zT value of 0.8 in 300 to 873 K, demonstrating the effectiveness of trace Ru doping on boosting the thermoelectric performance of ZrNiSn‐based alloys. [ABSTRACT FROM AUTHOR]

In this work, the electro-optical and magnetic characteristics of Be1-xCrxS (x = 6.25%, 12.5% and 25%) are brought into investigation by employing full potential linearized augmented plane wave (FP-LAPW) scheme designed within density functional theory (DFT). The stability of the Be1-xCrxS alloy is justified by the negative values of formation energy. The band structures and density of states are examined by using GGA functional. Be1-xCrxS compound demonstrates the half-metallic (HM) ferromagnetic behavior for all doping concentrations; spin-up channel reveals the metallic character and other spin version displays the semiconductor (SC) behavior. The values of total magnetic moment (µB) are recorded as 4.0 8.0 and 16.0 µB for corresponding 6.25%, 12.5% and 25%, which mainly arises owing to Cr-3d state. Moreover, optical features including dielectric function ε(ω), reflectivity, refraction, and absorption are explored within range of 0-10 eV. The maximum absorption of incident photons was found in ultraviolet (UV) span which implies their importance for optoelectronic applications. Results reveal that the studied alloy has potential applications in magnetic and optoelectronic gadgets. [ABSTRACT FROM AUTHOR]

Magnetization measurements were conducted on a ferromagnetic Co2NbGa with the Heusler-type structure at various pressures. The spontaneous magnetic moment (ps) at 10 K under ambient pressure was determined to be 1.79(3) μB/f.u. The values of dps/dp and dlnps/dp at 10 K were estimated to be –0.13 × 10–3 μB·f.u.–1·kbar–1 and –7.3 × 10–5 kbar–1, respectively. The pressure derivative of the Curie temperature (TC) for Co2NbGa was determined by analyzing the temperature dependence of the initial permeability under pressures ranging up to 10 kbar. At ambient pressure, Co2NbGa had a TC value of 374.8 K, with dTC/dp and dlnTC/dp values of –0.69 K·kbar–1 and –1.84 × 10–3 kbar–1, respectively. The experimental results of the pressure-dependent magnetic properties for Co2NbGa were discussed on the basis of the spin fluctuation theory for itinerant electron magnetism. [ABSTRACT FROM AUTHOR]

The mechanical and electronic properties of perovskite compounds Cs2KFeF6, Cs2KVF6, Cs2TiVF6 and Cs2TlVF6 were comprehensively studied. It was found that the four compounds have 100% spin polarizability in the equilibrium state, Cs2KFeF6 exhibits bipolar magnetic semiconductor with a band gap of 1.72 eV, and Cs2KVF6, Cs2TiVF6 and Cs2TlVF6 show half-metallic properties with half-metallic gap of 1.75 eV, 0.94 eV and 1.76 eV, respectively. All four compounds show mechanical stability and varying degrees of anisotropy, and calculations of the ideal tensile strength show that they resist well in one direction at different strains. It is found that Cs2KFeF6 exhibits stable semiconductor characteristics under strain and strong light absorption in visible region under tensile strain. Cs2KVF6, Cs2TiVF6 and Cs2TlVF6 maintain robust half-metallic properties throughout the strain interval. The total magnetic moments of the equilibrium and strains are always kept at integer values, and the transition metal atoms contribute the most to the total magnetic moments. The high spin polarizability, modulable visible light absorption and wider half-metallic gap of these four perovskite compounds indicate that have demonstrated significant potential and wide-ranging application prospects in the exploration of next-generation optoelectronic devices and spintronics. [ABSTRACT FROM AUTHOR]

We have looked at a very interesting class of Heusler alloy that has received a lot of theoretical research but a very little experimental attention. Mn2TiSi Heusler alloy was synthesized by a conventional vacuum arc remelting process. The formation of Heusler phase along with the secondary phases was observed after annealing it at 773 K for 120 h. The X-ray diffraction pattern illustrates the presence of cubic B2 disordered phase along with a secondary phase with a lattice parameter of 5.82 Å. The microstructure and compositional analysis of Mn2TiSi alloy shows the presence of distribution of Mn, Ti, and Si elements according to their stoichiometric ratio. The magnetic measurements show a ferromagnetic nature with Curie temperature (TC) around 203 K. With low magnetic moment and coercivity, Mn2TiSi can be used for switching applications because of its fast magnetization reversal. So, Mn2TiSi becomes the greatest choice for use in spintronics due to its low magnetic moment and low coercivity. [ABSTRACT FROM AUTHOR]

A comprehensive investigation is conducted on the electronic structure and magnetic properties of half‐Heusler NaScGe, which is doped with a rare earth element Nd with different concentrations. The Heusler Na1‐xNdxScGe (where x = 0, 0.25, 0.75, and 1) compounds are thoroughly investigated. The examination encompassed structural, elastic, magnetic, and electronic characteristics using the full potential linearized augmented plane wave (FP‐LAPW) method. Generalized gradient approximation (GGA) is used to calculate the structural parameters and electronic characteristics. The equilibrium lattice constant and band gap of half‐Heusler NaScGe are found to be in good accord with other data. The density of states (DOS) investigation has revealed a semiconductor behavior of half‐Heusler NaScGe and half‐metallic ferromagnetic properties of quaternary‐Heusler Na0.75Nd0.25ScGe, characterized by a moderate band gap in minority spin channel. In addition, the DOS analysis has shown that both ternary half‐Heusler NdScGe and QH Na0.25Nd0.75ScGe compounds have exhibited metallic ferromagnetic activity. The work has introduced a novel approach for producing half metals from the semiconductor half‐Heusler NaScGe. Quaternary‐Heusler Na0.75Nd0.25ScGe is identified as a promising material for applications spintronic. [ABSTRACT FROM AUTHOR]

In this paper, we investigated the structural and magneto-electronic properties, and exchange coupling in new vanadium (V)-doped PbTiO3 perovskite oxide such as PbTi1−xVxO3 compounds with compositions of x = 0, 0.25, 0.5, 0.75, and 1. The calculations of these properties are based on density functional theory using the generalized gradient approximation of Wu-Cohen (GGA-WC) and the Tran-Blaha-modified Becke–Johnson potential (TB-mBJ). Our calculations with GGA-WC revealed that the lattice constant for PbTiO3 is in good concordance with other theoretical and experimental results, while for PbTi1−xVxO3 at x = 0.25, 0.5, 0.75, and 1, the lattice constant decreases with increasing vanadium concentration owing to the difference in sizes of Ti and V ionic radii. The improved electronic structures obtained by employing the TB-mBJ potential, demonstrated that the half-metallic ferromagnetic and half-metallic gaps are present in PbTi1−xVxO3 materials at x = 0.25, 0.5, 0.75, and 1, which makes them promising candidate materials for spintronics applications. [ABSTRACT FROM AUTHOR]

The rare earth metal doped Si-based semiconductor clusters have aroused increased attention in a lot of fields. Here, the structural evolution, magnetic and spectral properties of bimetallic Eu2 doped silicon-based clusters, Eu2Sin− (1 ≤ n ≤ 12), have been investigated using artificial bees colony and Saunders "Kick" global optimization techniques associated with density-functional theory calculations. The calculations show that the two Eu atoms prefer to occupy the surface position of parent silicon clusters and form exohedral geometric structures. It is found that the structural growth pattern is reflected at n = 4–8 where the two Eu atoms lie on the framework of distorted pentagon. Eu2Si5− is determined to the most stable cluster owing to the strong interaction between host Si atoms and dual Eu atoms. The natural atomic orbital method reveals that the charges always transfer from the Eu to Si parent atoms. Interestingly, the total magnetic moments are not quenched but superimposed together with introduction into Si-based cluster, 4f electrons almost remain in two Eu atoms and hardly participate in the molecular Si–Eu bonding. Moreover, theoretical photoelectron spectra are predicted in order to provide a theoretical guidance for the future photoelectron spectroscopy experiments of double rare earth metal doped Si-based semiconductor clusters. [ABSTRACT FROM AUTHOR]

Double perovskite materials are particularly well suited for energy applications because of their nontoxic, efficient, and environmentally advantageous characteristics. Using the full-potential linearized augmented-plane-wave approach, Ba2DyTaO6 oxide double perovskite was thoroughly examined to investigate the microstructural, magnetic, and optoelectronic properties. The thermodynamic and structural stability was mapped by computing the phonon properties, tolerance factor, and octahedral factor, respectively, which revealed that Ba2DyTaO6 was highly stable. The results were determined based on the electronic and magnetic properties obtained from the data. The band edges at the same symmetry points indicated that there was a direct bandgap in the (ΓV–ΓC) direction in the majority spin, a value equal to 3.793 eV with an overlap in the minority spin. With an integer magnetic moment value of 5.00 μB, the Ba2DyTaO6 compound exhibits half-metallic and ferromagnetic behavior. This research is the first of its kind in terms of optical properties. It can be concluded that the Ba2DyTaO6 material has high absorption, and can be applied in future optoelectronic applications throughout a wide energy range of the light spectrum. Given the limited availability of theoretical and experimental data, the present investigation can provide value for future studies on this compound. Our findings can thus pave the way for additional investigations into the potential use of this oxide material in numerous chemical and physical applications intended for socioeconomic needs. [ABSTRACT FROM AUTHOR]

This work concerns innovative approach to prepare Pb–Sn–Ba grids for lead-acid batteries which provides their enhanced structural stability and mechanical properties allowing functionality and prolongation of service life at high temperatures. To have these properties in the Pb–Sn–Ba grids, two roll melt spinning technology is applied that provides a greater to extreme environments resistance to fatigue, higher mechanical properties, thermal (for high temperature exposure) stability. As a result, far less disposal and environmental hazard will be posed by longer-lived lead-acid batteries with the Pb–Sn–Ba grids prepared using melt spinning technology compared to those fabricated by conventional methods. [ABSTRACT FROM AUTHOR]

Heusler alloy is a ferromagnetic alloy based on the Heusler phase. It is an intermetallic alloy between metallic and non-metallic elements that can be non-ferromagnetic and has a BCC crystal structure. This paper presents the theory of thermodynamics and elastic deformation of full-Heusler A2BC alloy with BCC structure built on the basis of statistical moment method (SMM). The paper presents numerical results for the temperature and pressure dependence of the mean nearest neighbor distance between two atoms, the density, the volume, the thermal expansion coefficient, the isotherm and adiabatic compressibilities, the isothermal elastic modulus, the heat capacities at constant volume and pressure, Young's modulus, the bulk modulus, longitudinal and transverse wave velocities of alloys Co2TaGa and Co2VGa when using the coordination sphere method and the Mie–Lennard-Jones pair interaction potential. Some SMM calculation results agree well with available ab initio calculation results. [ABSTRACT FROM AUTHOR]

This document is an editorial from the journal "Metals" titled "Crystallography and Applications of Metallic Materials." It discusses the scientific and technological interest in metals and metallic alloys, highlighting their wide range of applications in fields such as mobility, biomedicine, heat transfer, energy, and sustainability. The special issue aims to present the current knowledge and trends in metallic materials based on crystallography development and analysis, focusing on the relationships between microstructure, properties, and applications. The document provides a summary of the contributions made by various manuscripts, covering topics such as crystal orientation, dislocation slip, phase transformations, corrosion behavior, nucleation, additive manufacturing, and magnetic properties. The editorial concludes by emphasizing the value of understanding the processing-microstructure-property relationships in the development and design of new metallic materials. [Extracted from the article]

The structural, dynamical, electrical, magnetic, and thermoelectric properties of CoMRhSi (M = Cr, Mn) quaternary Heusler alloys (QHAs) were investigated using density functional theory (DFT). The Y-type-II crystal structure was found to be the most stable configuration for these QHAs. Both CoCrRhSi and CoMnRhSi alloys possess a half-metallic behavior with a 100% spin-polarization as the majority spin channel is metallic. On the other hand, the minority spin channel is semiconducting with narrow indirect band gaps of 0.54 eV and 0.57 eV, respectively, along the Γ − X high symmetry line. In addition, both CoCrRhSi and CoMnRhSi alloys possess a ferromagnetic structure with total magnetic moments of 4 μB, and 5 μB, respectively, which are prominent for spintronics applications. The thermoelectric properties of the subject QHAs were calculated by using Boltzmann transport theory within the constant relaxation time approximation. The lattice thermal conductivities were also evaluated by Slack's equation. The predicted values of the figure-of-merit (ZT) for CoCrRhSi and CoMnRhSi were found to be 0.84 and 2.04 at 800 K, respectively, making them ideal candidates for thermoelectric applications. [ABSTRACT FROM AUTHOR]

Light transition metals have recently emerged as a sustainable material class for efficient spin–charge interconversion. We report measurements of current-induced spin–orbit torques generated by Ni1−xCux alloys in perpendicularly magnetized ferrimagnetic Gd/Fe multilayers. We show that the spin–orbit torque efficiency of Ni1−xCux increases with the Ni/Cu atomic ratio, reaching values comparable to those of Pt for Ni55Cu45. Furthermore, we demonstrate magnetization switching of a 20-nm-thick Gd/Fe multilayer with a threshold current that decreases with increasing Ni concentration, similar to the spin–orbit torque efficiency. Our findings show that Ni1−x Cu x − based magnetic heterostructures allow for efficient control of the magnetization by electric currents. [ABSTRACT FROM AUTHOR]

By using density functional theory, we have explored the structural, electro-mechanical, thermophysical and thermoelectric properties of CoZrSi and CoZrGe Heusler alloys. The ground state stability was determined by optimising the energy in various configurations like type I, II, and III. It was found that these alloys stabilized in the ferromagnetic phase in type I. We employed the Generalised Gradient Approximation and modified Becke-Johnson potentials to explore the electronic structure. The band structures of each of these Heusler alloys exhibit a half-metallic nature. Additionally, the computed second-order elastic parameters reveal their ductile nature of them. To understand the stability of the alloys at different pressures and temperatures, we investigated various thermodynamic parameters using the Quasi-Harmonic Debye model. We obtained the transport coefficients using the Boltzmann theory. Our findings indicate that these alloys can be used in spintronics and thermoelectric domains. [ABSTRACT FROM AUTHOR]

In this study, we investigate the effects of doping with ∼10 at% of Si, Al, Sn, and Bi on the atomic order, microstructure, and magnetic properties of CoMnSb samples prepared using the arc-melting method. X-ray diffraction, scanning electron microscopy, and magnetometry techniques were employed to derive the structural and magnetic parameters. The samples demonstrate a superstructure with an Fm -3 m space group. They exhibit a saturation moment of 3.71–4.71 μ B per formula unit at 5 K and a Curie temperature ranging from 474 to 507 K. Rietveld refinement performed on the XRD data revealed a possible occupation of magnetic atoms in the vacant 32 f (x ', x ', x ') sites and atomic swapping, both of which may affect the magnitudes of the magnetic moment and Curie temperature. The electrical measurement results show that the grain boundaries and voids govern the conductivity of the samples. The spin polarization of the Si-doped sample was determined based on the grain-boundary magnetoresistance effect, which showed that this sample has a high degree of atomic order, consistent with the low magnetic moment, Curie temperature, and lattice constant. [ABSTRACT FROM AUTHOR]