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In this article, we have conducted a comprehensive study on the structural, mechanical, electronic, magnetic and thermodynamic properties of the Heusler alloys FeZrTiZ ( Z = A l , G a , G e ). Our investigation utilize the GGA exchange correlational approximation functional. The results of our analysis indicate that among the Y1-, Y2- and Y3-type structures, the Y1-type structure exhibits stability and demonstrates ferromagnetic behavior. Furthermore, mechanical property analysis reveals that all alloys possess ductile characteristics. The analysis of the density of states of the Heusler alloys FeZrTiZ ( Z = A l , G a , G e ) demonstrates the presence of half-metallic nature in all of the alloys. Additionally, the investigated Heusler alloys exhibit integer spin magnetic moments. To study thermodynamic properties, we use quasi-harmonic approximation, which allows to analyze specific heat capacity, thermal expansion, Debye temperature, vibrational free energy, internal energy and entropy of the Heusler alloys FeZrTiZ ( Z = A l , G a , G e ). Overall, our findings provide a clear understanding of the structural, mechanical, electronic, magnetic and thermodynamic characteristics of Heusler alloys FeZrTiZ ( Z = A l , G a , G e ), shedding light on their potential applications in spintronics. [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]

Co 2 FeSi Heusler alloys have attracted a lot of attention due to their interesting properties for various technological applications. In this study, we present the results of ab-initio calculations of the electronic, structural and magnetic properties using generalized gradient approximations (GGA and GGA + U). The energies obtained from GGA are used to calculate the magnetic coupling and establish an effective Hamiltonian. Additionally, we utilized mean-field theory and Monte Carlo simulation to evaluate physical properties such as magnetization, susceptibility and critical exponent of the material from the effective Hamiltonian. The results indicate that Co2FeSi, which exhibits a half-metallic behaviour, may be suitable for use in spintronic applications. [ABSTRACT FROM AUTHOR]

The structural, half-metallic, and elastic characteristics of XZrAs (X = Cr, Mn, and V) half-Heusler compounds were theoretically calculated using the WIEN2k code. For the term of the potential exchange and correlation (XC), we calculated structural, electronic, and magnetic properties using the generalized gradient approximation (GGA). The type 1 arrangement in ferromagnetic (FM) phases is more energetically stable than other type arrangements in all compounds. The spin-up electrons of both XZrAs (X = Cr, Mn) half-Heusler compounds in the type III structure are semiconducting with energy gaps, whereas the spin-dn electrons are metallic. Research has also been done on the VZrAs compound, which exhibits metallic characteristics in both type I and type III structures. XZrAs (X = Cr, Mn, and V) half-Heusler compounds are elastically stable and ductile, according to calculated Cij elastic constants. Finally, at equilibrium lattice constants a = 6.1196 A° for MnZrAs and 6.142 A° for CrZrAs, real half-metal ferromagnetic materials (HMF) were produced from XZrAs (X = Cr, Mn) half-Heusler compounds within 3 µB and 2µB, respectively. [ABSTRACT FROM AUTHOR]

• The structural, magnetic, electronic and optical properties of half Heusler VXPt (X = Br, Se) alloys hae been studied. • Optimisation curves with negative formation energy show that the alloys under investigation are stable. • For VBrPt, an energy gap is present in major and minority spin carriers, while for VSePt, metallic character is seen in minority spin carriers. • An optical band gap with maximum absorption reveals that these alloys are useful for optoelectronics. High-spin polarized magnetic materials might be useful in spintronics applications. The spin-polarized magnetic, optical, electronic and structural attributes of half-Heusler VXPt (X = Br, Se) alloys were theoretically explored and calculated using the WIEN2k code. The ground states of the structures are optimized, and the bulk moduli and lattice constants are computed. The values obtained from the formation energies show their stability. For VBrPt, an energy gap is present in major and minority spin carriers, while for VSePt, major spin carriers exhibit an energy gap and metallic character is seen in minority spin carriers. The band structures are further illustrated deeply through the investigation of density of states. The electron density graphs depict the ionic bonding in both alloys. The magnetic moments are additionally assessed, and the recorded values support the magnetic characteristics of VBrPt and VSePt. The assessment of how the studied alloys react to light is determined by computing various parameters. The imaginary component and absorption coefficient anticipate substantial light absorption within the visible region. The calculated outcomes unveiled the potential of the examined alloys for applications in spintronics. [ABSTRACT FROM AUTHOR]

The structural, electronic, and magnetic properties of a new series CoRhZrZ quaternary Heusler were investigated theoretically by using the density of function theory calculation. All the compounds were found to be stable at the ferromagnetic phase. The magnetic moments of the compound show a positive value ranging from 1 to 2 μB. In addition, the electronic structure of CoRhZrSi shows a large value of the half‐metallic band gap of 0.34 eV. This reflects the high thermal stability of the compound at high temperatures and allowing for a wide range of applications of this material in varying domains, especially those requiring high thermal stability such as the oil and gas sectors, geological applications, and space applications. [ABSTRACT FROM AUTHOR]

In this work, we have successfully fabricated nanocrystalline Co2MnSi Heusler alloy glass-coated microwires with a metallic nucleus diameter (dnuclei) 10.2 ± 0.1 μm and total diameter 22.2 ± 0.1 μm by the Taylor–Ulitovsky technique for the first time. Magnetic and structural investigations have been performed to clarify the basic magneto-structural properties of the Co2MnSi glass-coated microwires. XRD showed a well-defined crystalline structure with a lattice parameter a = 5.62 Å. The room temperature magnetic behavior showed a strong in-plane magnetocrystalline anisotropy parallel to the microwire axis. The M-H loops showed unique thermal stability with temperature where the coercivity (Hc) and normalized magnetic remanence exhibited roughly stable tendency with temperature. Moreover, quite soft magnetic behavior has been observed with values of coercivity of the order of Hc = 7 ± 2 Oe. Zero field cooling and field cooling (ZFC-FC) magnetization curves displayed notable irreversible magnetic dependence, where a blocking temperature (TB = 150 K) has been observed. The internal stresses generated during the fabrication process induced a different magnetic phase and is responsible for the irreversibility behavior. Moreover, high Curie temperature has been reported (Tc ≈ 985 K) with unique magnetic behavior at a wide range of temperature and magnetic fields, making it a promising candidate in magnetic sensing and spintronic applications. [ABSTRACT FROM AUTHOR]

Using zone calculations in the FLAPS (the full-potential linearized augment- ed-plane-waves) model, information is obtained on the energy, charge and spin characteristics of Pt1-xMexMnSb alloys (Me = Ni, Au, x = 0.0--1.0). As established, with an increase in the concentration of nickel or gold atoms the interatomic spatial density of electrons decreases, covalent bonds weaken and the binding energies of atoms in alloys decrease. As found, the dominant con- tributions to the formation of magnetic moments are made by 3d electrons of manganese atoms, and the polarization of electrons at Fermi levels depends on the composition of alloys. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the electronic, magnetic, and optical properties of scandium based ternary oxides perovskite YScO 3 (Y = Ni, Pd, Pt). We employ the Tran and Blaha modified Becke-Johnson approximation to calculate spin polarization using the density functional theory. Based on the formation energy, we found that our materials are thermodynamically stable (−0.76 eV, −1.3 eV and −1.65 eV for NiScO 3 , PdScO 3 and PtScO 3 , respectively). The densities of states and spin polarized band structures for spin up (↑) and spin down (↓) channels reveal the half-metallic nature for all studied compounds with Ni/Pd/Pt-d orbitals playing a major role in the valence band. Additionally, all perovskites exhibit ferromagnetic behavior with magnetic moments approximately equal to 3 μ B. Moreover, we calculate several optical parameters such as the dielectric constants, refractive index, reflectivity, extinction and absorption coefficients for these compounds. The results suggest that these perovskites might be promising candidates for optical and spintronic devices. • YScO3 (Y = Ni, Pd, and Pt) are thermodynamically stable. • Exhibits half-metallic ferromagnetism with 100% spin polarization. • The structural, electronic, magnetic, and optical properties were investigated using density functional theory. • Promising candidates for spintronic applications. [ABSTRACT FROM AUTHOR]

Using DFT and Monte Carlo simulation, we studied the physical properties of the ferrimagnetic half-metal Mn 2 RhSi Heusler alloy. Our calculations reveal a stable face-centered cubic structure without any possibility of martensitic transition. The electronic structure shows half-metallic behavior with a band gap in spin-down of 0. 49 eV calculated using PBE and 0. 85 eV using the r 2 SCAN functional, and antiferromagnetic–ferromagnetic coupling with a Curie temperature of 460 K. The elastic constants and moduli decrease with temperature due to thermal expansion, but Mn 2 RhSi retains its mechanical stability. The dominance of metallic bonds, large band gap, high Curie temperature, low magnetic moment, and good mechanical properties make Mn 2 RhSi a promising candidate for spintronic applications at room temperature. • Mn 2 RhSi is an inverse Heusler ferrimagentic half-metal. • According to the r2SCAN functional, Mn 2 RhSi has a spin-down gap of 0.85 eV. • Curie temperature of Mn 2 RhSi calculated using Monte Carlo simulation is 460 K. • Mechanical properties indicate that Mn 2 RhSi is mechanically stable and ductile over the temperature range of 0–1000K. • The wide gap and Curie temperature above room temperature suggest that Mn 2 RhSi can be suitable for spintronic applications. [ABSTRACT FROM AUTHOR]

We investigated the structural, magneto-electronic, and thermoelectric properties of V2CoZ (Z = Ga, and Ge) Heusler alloys using the ab-initio method. The XA-type structure within the ferrimagnetic phase is more energetically stable than other phases through the chemical stability so the negative value of energy formation that both compounds are favorable and synthesizable experimentally. Both compounds' mechanical properties show anisotropic ductile materials. In addition to their half-metallic ferrimagnetic behavior with an integer total magnetic moment, according to magneto-electronic calculations. Boltzmann's transport theory was also used to investigate the thermoelectric response. Our findings show that these Heusler alloys have a lot of potential for thermo-spintronic devices. [ABSTRACT FROM AUTHOR]

Conventional spin-transfer torque-based magnetoresistive random access memory (STT-MRAM) with CoFeB electrodes has great potential as universal memory. However, state-of-the-art STT-MRAM technology has encountered the issues such as high writing current density and low thermal stability for scaling down to $1\times $ nm. Heusler alloy has been suggested as an alternative to resolve these problems by significantly reducing the Gilbert damping constant while preserving approximately 100% spin polarization. In particular, $L2_{1}$ -ordered Co2FeAl (CFA)-based magnetic tunnel junction (MTJ) exhibits outstanding half-metallicity and perpendicular magnetorcystalline anisotropy characteristics arising from Co(Fe)-O orbital hybridization at the interface. In this work, we investigate the biaxial strain effects of CFA-based MTJ by adjusting in-plane lattice constants from −4% to +4%. Our density functional theory - nonequilibrium Green’s function (DFT-NEGF) calculations present that FeAl-O interfaced MTJ shows a converged tunneling magnetoresistance (TMR) ratio under compressive strain while Co2-O interfaced MTJ shows strain-sensitive TMR ratio under both compressive and tensile strain. The difference in the current-density trends for the two types of MTJs is mainly attributed to the additional state arising from Fe-O bonding. Our results emphasize the careful control of straintronic techniques on CFA-MTJs. [ABSTRACT FROM AUTHOR]

With the intention to reveal the effect of the substitution, Ti-doped InSb alloy, we accomplished a first-principles prediction within the FPLAPW+lo method. We used GGA-PBEsol scheme attached with the improved TB-mBJ approach to predict structural, electronic, and magnetic properties of In1-xTixSb with concentration x = 0, 0.125, 0.25, 0.50, 0.75, 0.875, and 1. Our lattice parameters are found in favorable agreement with the available theoretical and experimental data. The calculation shows that all structures are energetically stable. The substitutional doping transforms the ionic character of the InSb compound in half-metallic ferromagnetic comportment for concentration x = 0, 0.125, 0.25, and 0.50, with a spin polarization of 100% at the Fermi level, and metallic nature for In0.25Ti0.75Sb and In0.125Ti0.875Sb. The total magnetic moments are also estimated at about 1 μB. In0.875Ti0.125Sb, In0.75Ti0.25Sb, and In0.50Ti0.50Sb have half-metallic ferromagnets comportment and they can be upcoming applicants for spintronics applications. [ABSTRACT FROM AUTHOR]

In this paper, the LiMg0.95TM0.05N alloy (TM=Ti, V, and Cr) undergo the Korringa-Kohn-Rostoker framework and "coherent potential approximation" to examine the magnetic and electronic behaviors, based on the MACHIKANEYAMA2002v09 program. In LiMg0.95TM0.05N alloy, the N ions around TM ions form a zinc-blende structure crystal field, which causes the Ti[d], V[d], and Cr[d] orbitals to split into the lower doubly degenerate eg(dx2-y2,dz2) and higher triply degenerate t2g(dxy,dyz,dxz) states. The "electron spin polarization (P)" of TM[d] is around the Fermi energy (Ef) and exhibits the half metallic characteristic, and the ferromagnetic stability is depicted in LiMg0.95TM0.05N. Also, the computed magnetic and the Curie temperature are valuable at room temperature as promised ferromagnetic material. The obtained values are 541.05 and 453.23 K connected to LiMg0.95V0.05N and LiMg0.95Cr0.05N, respectively. For the LiMg0.95TM0.05N alloy, the exchange splitting ∆ Ex TM is larger than the crystal field splitting ∆ CR TM , where ∆ Ex Cr > ∆ Ex V > ∆ Ex Ti and ∆ CR Cr > ∆ CR V > ∆ CR Ti . Also, total spin moment is arranged as follows: M LiMg 0.95 Cr 0.05 N Total > M LiMg 0.95 V 0.05 N Total > M LiMg 0.95 Ti 0.05 N Total. [ABSTRACT FROM AUTHOR]

In this paper, an ab initio study of the electronic and magnetic properties of CdS doped by the transition metal elements has been investigated. Based on the KKR-CPA method within the Generalized Gradient Approximation (GGA), we have calculated the total energy to determine the most stable state in the system and found it to be the ferromagnetic state for Ti, V and Cr-doped CdS, while it is the stabilization in spin glass states for Mn and Co cases. On the other hand, we have investigated and plotted the density of states (DOSs) which reveals that the doped compounds exhibit a half-metallic character. The spin polarization at Fermi level is estimated and found to be around 100%. Furthermore, we have identified the type of mechanism of exchange interactions being double exchange for all components except Mn case where we find that the responsible mechanism is the p-d exchange. The evaluation of the Curie temperature variation TC for the three components stable in the ferromagnetic phase revealed values greater than 300 K for most cases. The effect of the crystal field and the exchange splitting as a function of the concentrations values has been also investigated. Half-metallic substances are very interesting for spin-dependent electronics devices as they boost their magnetoresistance capacity. [ABSTRACT FROM AUTHOR]

• Enhance the electronic and magnetic attributes of B 4 C 3 by introducing 4d TMs. • The assessment of stability for the pristine B 4 C 3 material. • Single TMs and 2TMs adsorbed B 4 C 3 demonstrate different characteristics. • The charge distribution has been assessed using Hirshfeld charge analysis. We conducted a systematic investigation of B 4 C 3 adsorbed with 4d-transition metals (4d-TMs), including Tc, Cd, Mo, Nb, Rh, Ru, and Ag, using first principles. This study involved an evaluation of structural, electronic, and magnetic properties. When single atom adsorption was adsorbed to B 4 C 3 using elements such as Tc, Nb, Rh, Ru, and Ag, it demonstrated characteristics of a diluted magnetic semiconductor (DMS), manifesting magnetic moments. Conversely, Cd, Mo, and Pd exhibited behavior consistent with non-magnetic semiconductors. Ferromagnetic (FM) and antiferromagnetic (AFM) arrangements were formed through the adsorption of 2TM atoms on B 4 C 3. In the FM setup, Ru and Nb uphold their roles as DMS. Interestingly, Tc and Rh exhibit half-metal behavior in this configuration, displaying their potential utility in spintronics applications. In the AFM configuration, Tc displayed half-metallic behavior, while the other metals maintained the same characteristics observed in the case of single TM adsorption. The reactivity of Nb-B 4 C 3 is notably high owing to its low work function, whereas Cd-B 4 C 3 is observed to be less reactive. AFM coupling is favorable in the 2Nb-, 2Rh-, and 2Ru-B 4 C 3 systems, while 2Tc-B 4 C 3 displays FM coupling. Transition metals belonging to the 4d series hold the potential to enhance the properties of B 4 C 3 , including its half-metallic, metallic, and semiconductor characteristics. These findings suggest the potential use of 4D transition metals adsorbed on B 4 C 3 as a prospective material for spintronics and magnetic storage applications in the future. [ABSTRACT FROM AUTHOR]

This ab‐initio investigation presents the effect of substitution of Zr by Nb atom on the structural, electronic, magnetic, and transport properties of the quaternary Heusler CoZrFeSi alloy. The ab‐initio calculations were performed using the exchange‐correlation of the modified Becke‐Johnson potential. Our results predict that the crystalline phase for each of CoZrFeSi and CoNbFeSi alloys is classified as Type‐I. The calculated formation energy value of the Nb‐doped alloys indicates the thermodynamic stability of the alloys and their possible creation. The bulk modulus value predicts that the rigidity increases with increasing the concentration of the Nb substitute atoms in the alloy. The electronic band structure and the density of states indicate a half metallicity of the alloys with metallic and semiconducting behaviors in the spin up and down, respectively. The studied alloys have shown ferromagnetic character with a high magnetic moment value when increasing the Nb content up to 75%. The calculated Seebeck coefficient and the charge carrier concentration as a function of temperature predict that the present alloys prefer the n‐type doping with the ability to switch between hole and electron for transporting the charges through the Fermi level of CoZr1−xNbxFeSi (x = 0, 0.25, 0.75, and 1) alloys. However, CoZr0.5Nb0.5FeSi alloy prefers electrons as a charge carrier. Due to their determined properties, beneficial applications are predicted for the present alloys, such as magnetic tunnel junctions and spintronic applications. [ABSTRACT FROM AUTHOR]

The first-principle calculations were performed in the framework of the density functional theory (DFT) using FP-LAPW method as implemented in Wien2k code to determine the structural stability, electronic, and magnetic properties of quaternary Heusler alloys Cr2TaGe1-xSnx (x = 0, 0.25, 0.50, 0.75, 1.00), The results showed that for the compounds, the AlCu2Mnl-type structure is energetically more stable than CuHg2Ti-type structure at the equilibrium volume. The calculated lattice constants for Cr2TaGe and Cr2TaSn are 6.081 Å and 6.311 Å, respectively. For mechanical properties, shear modulus, Young's modulus, elastic constants, Poisson's ratio and shear anisotropy factor have studied. Their obtained values reveal that these compounds are mechanically stable. The electronic band structures and density of states of our compounds show a half metallic character with total magnetic moments, − 3.00 μB per formula unit with indirect band gap, 0.569 eV and 0.482 eV for Cr2TaGe and Cr2TaSn respectively. Regarding thermal properties such as the thermal expansion coefficient, heat capacity, and Debye temperature, we have applied a very suitable model for studying thermodynamics quantities called the quasi-harmonic Debye model. On the basis of these results, these alloys are predicted to be good candidates for future spintronic 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]

In this work, we investigated the phase transition and electronic structures of some newly designed all-d-metal Heusler compounds, X2MnTi (X = Pd, Pt, Ag, Au, Cu, and Ni), by means of the first principles. The competition between the XA and L21 structures of these materials was studied, and we found that X2MnTi favors to feature the L21-type structure, which is consistent with the well-known site-preference rule (SPR). Under the L21 structure, we have studied the most stable magnetic state of these materials, and we found that the ferromagnetic state is the most stable due to its lower energy. Through tetragonal deformation, we found that the L21 structure is no longer the most stable structure, and a more stable tetragonal L10 structure appeared. That is, under the tetragonal strain, the material enjoys a tetragonal phase transformation (i.e., from cubic L21 to tetragonal L10 structure). This mechanism of L21-L10 structure transition is discussed in detail based on the calculated density of states. Moreover, we found that the energy difference between the most stable phases of L10 and L21, defined as ΔEM (ΔEM = ECubic-ETetragonal), can be adjusted by the uniform strain. Finally, the phonon spectra of all tetragonal X2MnTi (X = Pd, Pt, Ag, Au, Cu, and Ni) phases are exhibited, which provides a powerful evidence for the stability of the tetragonal L10 state. We hope that our research can provide a theoretical guidance for future experimental investigations.

The half‐metallicity of Heusler alloys is quite sensitive to high pressure and disorder. To understand this phenomenon better, we systematically studied the half‐metallic nature, magnetism, phonon, and thermomechanical properties of FeCrTe and FeCrSe Heusler alloys under high pressure using ab initio calculations based on density functional theory. The ground‐state lattice constants for FeCrTe and FeCrSe alloys are 5.93 and 5.57 Å, respectively, consistent with available theoretical results. Formation energy, cohesive energy, elastic constants, and phonon dispersion confirmed that both compounds are thermodynamically and mechanically stable. The FeCrTe and FeCrSe alloys showed a half‐metallic character with a band gap of 0.68 and 0.58 eV at 0 GPa pressure, respectively, and magnetic moments of 2.01 μB for both alloys, using generalized gradient approximation (GGA) approximation. FeCrTe alloy changes from metallic to half‐metallic above 30 GPa pressure using GGA + U. The elastic properties were scrutinized, and it was found that, at 0 GPa pressure, FeCrTe is ductile, and FeCrSe is brittle. Under pressure, FeCrSe becomes brittle above 10 GPa pressure. Average sound velocity Vm, Debye temperature ƟD, and heat capacity CV were predicted under pressure. These outcomes will improve the integration of Fe‐based half‐Heusler alloys in spintronic devices. [ABSTRACT FROM AUTHOR]

The inverse Heusler alloys such as Ti2CoSi, Mn2CoAl and Cr2ZnSi were studied in the framework of density functional theory using FP-LAPW linearised augmented plane wave method in order to determine the different physical properties such as structural, electronic, magnetic and thermoelectric. The generalised gradient approximation (GGA) was used to treat the exchange–correlation energy and the Beck-Johnson (mBJ) approach was used to calculate the electronic properties. In all studied compounds, the stable type Hg2CuTi was energetically more favourable than Cu2MnAl type structure. The results show that two compounds (Ti2CoSi and Mn2CoAl) are both ferromagnetic (FM) while Cr2ZnSi is antiferromagnetic (AFM). The compounds Ti2CoSi and Mn2CoAl have a total magnetic moment of 3 and 2 μB, respectively, whereas the Cr2ZnSi alloy has a total magnetic moment equals zero. The Ti2CoSi, Mn2CoAl and Cr2ZnSi compounds exhibit half-metallic (HM) character with 100% spin polarisation at the Fermi level. Finally, the semi-classical Boltzmann theory implicit in the BoltzTraP code was used to calculate the electronic transport coefficients such as thermal and electrical conductivity, the Seebeck coefficient and the factor of merit. [ABSTRACT FROM AUTHOR]

First-principles calculations based on density functional theory (DFT) confirm the half-metallic ferromagnetism in both Co 2 TiSn and Co 2 VSn , and the nearly half-metallic ferromagnetism in Co 2 CrSn Heusler alloys with the AlCu 2 Mn -type structure ( L2 1). The electronic band structures and density of states (DOS) calculations of the Co 2 TiSn and Co 2 VSn compounds show that the spin-up electrons are metallic, whereas the spin-down bands are semiconducting with a gap of 0.47 eV and 0.53 eV, respectively, with 0.21 eV and 0.36 eV as a spin-flip gap, respectively. The Co 2 TiSn and Co 2 VSn Heusler were half-metal compounds with magnetic moment of 2   μ B and 3   μ B at the equilibrium lattice constants a = 6. 0 9 7  Å and a = 6. 0 2 6  Å, respectively, which agrees with the Slater–Pauling rule, and have 100% polarization for a wide range of lattice parameters. The Co 2 CrSn is a nearly half-metal (NHF) compound with magnetic moment of 4. 0 1   μ B and 92.9% polarization at the equilibrium lattice constants a = 5. 9 9 5  Å and acquire half-metal behavior under the pressure 16.70 GPa. [ABSTRACT FROM AUTHOR]

Spintronic is the developing technology which probes the properties of quantum devices with spin of electrons which reduce the size and enhance its speed. Therefore, here the role of 5d electrons and thermoelectric characteristics of double perovskites (DPs) K 2 ZCl/Br 6 (Z = Ta, W, Re) elaborated comprehensively by density functional theory (DFT). The Heisenberg model spin polarization density (SP) has been applied to evaluate the Curie temperature (T c) and spin polarization factor. The tolerance factor (t F) and formation energy (ΔH) have been calculated to confirm the stability of structures. Ferromagnetism has been discussed in terms of spin polarization, crystal field energy (Δ CF) and exchange energies (Δ(d), Δ(pd)). The double exchange mechanism, and exchange constants ensure the role of electrons spin in ferromagnetism instead of segregation of transition metal ions. The transferring of magnetic moments of transitions metals to nonmagnetic sites (K, Cl, Br) show the exchange of spin of electrons and integer values of total magnetic moment show 100 % spin polarization. Finally, the transport properties are studied in standings of electrical and thermal conductivities. The large value of Seebeck coefficient and power factor ensure the importance of studied DPs for thermoelectric generators. • Spintronic and energy harvesting applications. • Large value of Curie temperature and high spin polarization. • The ferromagnetism by electron spin instead of magnetic ion clustering. • Half metallic ferromagnetism evidence complete spin polarization. • Ultralow low values of thermal conductivity and Large power factor. [ABSTRACT FROM AUTHOR]

The structural, electronic, and magnetic properties of Ti2RhSn1-xSix, Ti2RhSn1-xGex, and Ti2RhGe1-xSix (x = 0, 0.25, 0.5, 0.75, and 1) quaternary Heusler alloys have been investigated using first-principles density functional theory within generalized gradient approximation (GGA) and local spin-density approximation with Hubbard-U corrections (LSDA+U). The calculations have been performed using the full-potential linearized augmented Plane wave plus local orbitals method. The crystal structures of Ti2RhSn1-xSix, Ti2RhSn1-xGex, and Ti2RhGe1-xSix were found to be cubic in (F-43m) symmetry for x = 0, 1 and cubic in (P-43m) symmetry for x = 0.25, 0.75, while tetragonal in (P-4m2) symmetry for x = 0.5. The results show that all Ti2RhSn1-xSix, Ti2RhGe0.75Si0.25, and Ti2RhGe alloys are half-metallic ferrimagnetic. These new materials are good candidates for potential applications in spintronic. [ABSTRACT FROM AUTHOR]

The mechanical stability and physical properties of Co2V1−xZrxGa (x = 0, 0.25, 0.50, 0.75, 1) have been predicted by using ab initio calculations based on density functional theory. The exchange-correlation potentials are treated within the generalized gradient approximation-Perdew-Burke and Ernzerhhof (GGA-PBE) and Hubbard coefficient (GGA+U). The investigated minimum lattice parameter of Co2VGa is 5.8030 Å, which is in excellent agreement with available experimental and theoretical data and for Co2V1−xZrxGa (x = 0.25, 0.50, 0.75, 1) are 5.9026, 5.9625, 6.0060 and 6.0021 Å, respectively, which are predicted for the very first time. The total magnetic moments decrease with increasing concentration of x in Co2V1−xZrxGa, in agreement with the Slater-Pauling rule. Band structure and density of states calculations show that the minority spin channel exhibits band gaps of 0.43, 0.46, 0.52, 0.54 and 1.01 eV for GGA+U scheme around the Fermi level confirming that all the studied composites are half-metallic in nature. In this study, we also studied the elastic constant and it is established that all the materials are mechanically stable and ductile in nature. The Co2VGa is stiffer than other materials and all the studied composites have anisotropic behaviour. Moreover, by using a quasi-harmonic Debye model and calculated elastic constant, the Debye temperature and temperature-dependent constant volume heat capacity have been investigated. [ABSTRACT FROM AUTHOR]

Spintronic is the emerging technology for next generation electronic devices that can improve memory and computing capability by use of electrons spin degree of freedom. The electronic, magnetic, and transport properties of MgEu 2 (S/Se) 4 spinels are explored systematically. These spinels are stable in ferromagnetic state (FM) confirmed by energy release in optimization, phonons band structures, and enthalpy of formation (ΔH f). The Curie temperature and spin polarization signify spin polarization at high temperature. The hybridization of p-S/Se and f-Eu states have been discussed from Band structure, and density of states which explain the nature of ferromagnetism. The crystal field and exchange energies are also reported for the verification of control of electrons spin. Furthermore, the exchange constants, and double exchange mechanism also premeditated. The double exchange model is satisfied by the negative Δ x (pf) and constant N o β. Moreover, the Seebeck coefficient, conductivities, and power factor (PF) for spin (↑) and spin (↓) are investigated separately and collectively by BoltzTraP code. The high values of PF and ultralow values of thermal conductivity make the potential materials for thermoelectric generators. • The role rare earth elements in ferromagnetism, and spintronic applications. • Use of materials as magnesium ion batteries and energy storage. • The ferromagnetism by electron spin instead of magnetic ion clustering. • Half metallic ferromagnetism evidence 100% spin polarization. • Ultralow low thermal conductivity increases the importance for device fabrication. [ABSTRACT FROM AUTHOR]

In this research work, we have predicted the physical properties of CoFeZrGe and CoFeZrSb for the first time by utilizing first principle calculations based on density functional theory. The exchange-correlation potentials are treated within the generalized-gradient approximation of Perdew-Burke and Ernzerhof (GGA-PBE). The investigated equilibrium lattice parameters of CoFeCrSi are in agreement with available theoretical data and for CoFeZrZ(Z = Ge,Sb) are 6.0013 and 6.2546 Å respectively. The calculated magnetic moments are 1.01 μ B / fu , 2 μ B / fu and 1 μ B / fu for CoFeZrZ(Z = Ge, Sb and Si) respectively, and agree with the Slater-Pauling rule, M t = Z t - 24 . The CoFeZrGe, CoFeZrSb and CoFeZrSi composites showed half-metallic behaviour with 100 % spin polarization at equilibrium lattice parameters with band gap of 0.43, 0.70 and 0.59 eV for GGA and an improved band gap of 0.86, 1.01 and 1.08 for GGA + U respectively. Elastic properties are also discussed in this paper and it is found that all the materials are mechanically stable and ductile in nature. The CoFeZrSi alloy is found to be stiffer than CoFeZrZ(Z = Ge and Sb) alloys. The Debye temperatures are predicted by using calculated elastic constants. Moreover, the volume heat capacities ( C v ) are investigated by utilizing the quasi-harmonic Debye model. [ABSTRACT FROM AUTHOR]

The electronic structures and magnetic properties of CoMnTaSi and CoMnTaGe Heusler alloys with LiMgPbSb-type structure investigated firstly by using the first-principles calculations. We have applied the full-potential linearized augmented plane waves plus local orbitals (FP-L/APW+LO) method. Exchange-correlation effects are treated using the generalized gradient approximations GGA and GGA+ U. The GGA calculation shows the CoMnTaSi and CoMnTaGe compounds at its equilibrium lattice constant are HM ferromagnet with an indirect band gap Γ → X of 0.34 and 0.39 eV and a HM gap of 0.34 and 0.13 eV in the spin-down channel. The CoMnTaZ (Z = Si, Ge) compounds have an integer total magnetic moment of 1.00 μB, satisfying the Slater-Pauling rule mtot = ( Nv − 24). The similar results are also obtained by GGA+ U calculation. Therefore, these new materials are good candidates for potential applications in spintronic. [ABSTRACT FROM AUTHOR]

The electronic structure and mechanical properties of some cobalt-based binary half-Heusler alloys Co2X (X = In, Si, Sb, Sn, Ga) have been investigated using the density functional theory approach. The site preference by cobalt and X is similar to the traditional half-Heusler structure. The results showed that Co2 Si is not a half-metal but rather an n-type degenerate semiconductor. The compounds Co2Ga, Co2Sb, and Co2Sn are thermodynamically unstable and Co2 In is elastically unstable. With much care given to the lattice size, half metallicity is readily predicted in Co2 In, Co2Ga, Co2Sn, and Co2Sb. All the compounds showed directional bonding and they should exhibit high strength. The trend is that the low valence main group elements are likely to form half metals more readily in a binary half-Heusler alloy than the high valence main group elements. [ABSTRACT FROM AUTHOR]

We present a quantum-mechanical first-principle calculation of the structural, elastic, electronic, and magnetic properties of the full-Heusler compounds TiNi X ( X= Al, Ga, and In). The calculation uses the full-potential linearized augmented plane waves plus local orbital method to describe Ti-based Heusler alloys. The results show that these compounds exhibit half metallic characteristics over a wide range of mesh parameters and obey the Slater-Pauling rule, which states that the total magnetic moment per unit cell M = Z − 18 for half-Heusler compounds XYZ and M = Z − 24 for full-Heusler X YZ compounds. For these new alloys TiNi X ( X= Al, Ga, and In), we initially considered the two possible L2 structures AlCuMn and CuHgTi. However, two subsequent structural studies showed that only the CuHgTi-like structure is half metallic. Over a wide range of mesh parameters, the calculations give a total magnetic moment of 3.00 μ . These results suggest that TiNi X ( X= Al, Ga, and In) are promising materials for spintronic applications. [ABSTRACT FROM AUTHOR]

Between the ferromagnetic semiconductors of the III-V group, the transition metals (TMs) doped aluminum nitride (Al, TM)N diluted magnetic semiconductor (DMS) is the most well understood and promising applications in spintronic, due to its high Curie temperature. In this research, electronic and magnetic properties of pure armchair (4, 4) and zigzag (6,0) aluminum nitride Nanosheets (AlNNS) and doped with transition metals are investigated using the spin-polarized density functional theory. The spin-polarized DOS revealed that pure AlNNS is a nonmagnetic semiconductor with a direct bandgap, while transition metals doped AlNNS are DMS or Half Metals (HM). Our results show a high Curie temperature more than 2000 K for Cu, Cr and Mn doping, indicating may be good room-temperature ferromagnetic material for spintronic applications in the future. 4.16% V and Ni atoms and 8.33% of Mn atoms doped AlNNS are HM with 100% spin polarization and appear to be good candidates for spintronic applications and especially as spin filter devices. • AlN Nanosheet doped with 4.16% and 8.33% transition metal atoms. • The doped AlN Nanosheet is diluted magnetic semiconductor or half metal. • Cu, Cr and Mn doped AlN Nanosheet are good for spintronic applications because of high Curie temperature. • V, Ni and Mn doped AlN Nanosheet exhibite half metallic property. [ABSTRACT FROM AUTHOR]

Heusler alloys exhibit diverse functional properties originating from magneto-elastic coupling and attracted significant interest in spintronic applications. We use the full-potential linearized augmented plane wave method to study the electromagnetic, structural, optical and thermoelectric properties of full Heusler Co 2 VGe alloy. The spin-polarized calculations and the spin-orbit coupling effect (SOC) are carried out to study the properties. The optimization is done in both ferromagnetic and non-magnetic states. The electronic structure shows the full-polarization at the Fermi level and confirms the half-metallic nature of Co 2 VGe. A band-gap of 0.89eV is achieved in spin-dn states with mBJ and it decreases with SOC up to 0.82eV. The Cobalt-atoms show major contribution to the overall magnetic behavior of the alloy. The optical and the thermoelectric response of Co 2 VGe are also calculated. In spin-dn states, a high value of Figure of merit i.e. 0.86 is obtained with mBJ and 0.77 with SOC effect at 800 K. • Investigation of the spin-polarized structural, electronic, magnetic and optical properties of full-Heusler Co 2 VGe alloys is done by first principles calculations with spin-orbit coupling effect. • The electronic band structure and density of states (DOS) shows the half-metallic nature of the alloys with mBJ potantial. • The optical parameters such as real and imaginary parts of dielectric function, refractive index, extension coefficients, and energy loss are also calculated. • The high value of ZT in the spin-dn states shows the possibility to use Co 2 VGe in thermoelectric devices. [ABSTRACT FROM AUTHOR]

In this paper, we employed density functional theory using WIEN2k to study structural, mechanical, electrical, magnetic and thermoelectric properties for quaternary Heusler alloys C o Z r T i X (X = G a , S i , S n). The self-consistent field calculation is done with generalized gradient approximation procedure. The structural stability analysis shows that the C o Z r T i X (X = G a , S i , S n) Heusler alloys are stable in Y-I type structure and having ferromagnetic property. In mechanical stability analysis we identified that all the reported Heusler alloys are ductile in nature. Electronic property calculations of C o Z r T i X (X = G a , S i , S n) reveals that all are half-metal, having metallic nature in spin up channel and semiconducting nature in spin down channel. The calculated values of spin magnetic moments are consistent with Slater-Pauling rule. From the transport properties, we identified that both alloys C o Z r T i G a and C o Z r T i S n are showing better thermoelectric performance in higher temperature, while the alloy C o Z r T i S i having reasonable Z T value at room temperature. Hence the reported Heusler alloys C o Z r T i X (X = G a , S i , S n) can be potential candidates for spintronic and thermoelectric applications. • Investigation of spintronic and thermoelectric properties of Heusler alloys CoZrTiX (X = G a , S i , S n). • Heusler alloys CoZrTiX (X = G a , S i , S n) showing half metallic nature with indirect band gap. • All the reported Heusler alloys CoZrTiX (X = G a , S i , S n) showing integer magnetic moments. • The figure of merit values Z T = 2.10, 0.18 and 1.85 for CoZrTiX (X = G a , S i , S n) respectively. • Potential alloys for both spintronic and thermoelectric applications. [ABSTRACT FROM AUTHOR]

Density functional theory based on the full-potential linearized augmented plane wave (FP-LAPW) method is used to investigate the structural, magnetic, electronic, and elastic properties of Heusler alloys CoYIn (Y = Ti, V). It is shown that the calculated spin magnetic moments using the local spin-density approximation (LSDA), generalized gradient approximation (GGA), LSDA + U, and Tran-Blaha (TB)-modified Becke-Johnson (mBJ)-local density approximations (LDA) are in good agreement with the Slater-Pauling rule. The obtained results with LSDA, GGA-PBE, and LSDA + U of the density of states illustrate that both compounds have a metal behavior; however, mBJ-LDA predicts CoVIn alloy to be a half metal. The band structure obtained with mBJ-LDA has an indirect band gap along the Γ- X symmetry with energy of 0.4 eV for CoVIn, and E lies in the middle of the gap; the electrons at the Fermi level are fully spin-polarized. The calculation of elastic properties indicates the stability of these compounds, and they have a ductile behavior. The 3D dependences of Young's modulus exhibit a strong anisotropic character. The high values of the elastic constant C reflect the strength of the bonding Ti (V)-In. [ABSTRACT FROM AUTHOR]

• Co2HfZ compounds were computationally designed as one of the advanced materials for spintronics. • Band structures, mechanical and magnetic character are presented. • The thermodynamic properties of all compounds under study are investigated. • d -states of 3d transition metals influence the formation of spin-down bandgap. The aim of this paper is the prediction of the electro-magnetic and mechanical properties of the Co2HfZ (Z = Al, Ga, Si and Sn) full Heusler compounds. For the structural and mechanical properties, we used the PBE-GGA schemes to compute the fundamental parameters, while for the electro-magnetic properties, we employed the modified Becke–Johnson (mBJ). Our results showed the half-metallicity of Co2HfZ (Z = Al, Ga, Si and Sn). The mechanical properties indicate that our compounds were anisotropic ductile materials. The present detailed investigation confirms that these compounds are a potential candidate for electro-spintronic applications. [Display omitted] The aim of this paper is the prediction of the structural, electro-magnetic and mechanical properties of the Co 2 HfZ (Z = Al, Ga, Si and Sn) full Heusler compounds using a full-potential linearized augmented-plane wave method (FP-LAPW) based on the Wien2k program. For the structural and mechanical properties, we used the Perdew-Burke-Ernzerhof Generalized Gradient Approximation (PBE-GGA) and modified Becke and Johnson (mBJ) schemes to compute the fundamental parameters. The latter was employed for the electro-magnetic properties, to calculate the band structures (BS) and density of states (DOS) of these compounds. Our results showed the half-metallicity of Co 2 HfZ (Z = Al, Ga, Si and Sn). The obtained energy revealed that these alloys were thermodynamically stable and could be hence elaborated experimentally. The mechanical properties indicated that our compounds were anisotropic ductile materials. Our findings greatly support that these compounds are highly attractive potential candidates for electro-spintronic applications. [ABSTRACT FROM AUTHOR]

• The physical properties of CoMnZnSi have been investigated using ab-initio calculations. • The CoMnZnSi alloy is chemically and dynamically stable. •.The calculations of electronic structure reveal that this alloy is perfect half-metallic. • Co (1 1 1) and Si (1 1 1)-surfaces show semi-metallic nature. The structural stability, electronic structure, and magnetic and optical properties of CoMnZnSi quaternary Heusler alloy (QHA) in the bulk and (1 1 1)-slab forms have been investigated by performing density functional theory (DFT) calculations. Formation and cohesive energies, and elastic constants confirm that the bulk CoMnZnSi is chemically and mechanically stable at an equilibrium lattice parameter of 5.81 Å. The calculated elastic constants also indicate that this QHA has ductile and anisotropic features. We investigate and discuss the bonding behavior from charge density distribution and density of states. These calculations in the bulk phase show a perfect half-metallic behavior with an integer value of magnetic moment (4 µ B) and a large spin-flip gap of 0.39 eV. On the other hand, the Co (1 1 1) and Si (1 1 1)-slabs exhibit semi-metallic nature at the Fermi level. These results indicate that CoMnZnSi qualifies for spintronic applications. In the bulk and Co (1 1 1), Zn (1 1 1), and Si (1 1 1)-surfaces, the magnetic moment of Co and Mn atoms are ferromagnetically aligned, while the ferrimagnetic alignment of Co with Mn has been found in Mn (1 1 1)-surface. We also investigate the optimal conductivity, dielectric functions, reflectivity, absorption coefficient, refractive index, and loss function to understand the underlying optical properties of this alloy. [ABSTRACT FROM AUTHOR]

In this paper, we used an ab-initio calculation within the Density Functional Theory (DFT) based on full-potential linearized augmented plane wave (FP-LAPW) method, to compute the magneto-electronic, elastic, thermic and thermoelectric properties of Ru 2 CrAl Heusler alloy, in L2 1 cubic structure. We calculated these properties within the general gradient approximation method (GGA) and GGA + U (U: Hubbard parameter). Furthermore, we added the modified Becke–Johnson approximation (mBJ) to study the electronic structure of our compound. The electronic properties show a half-metallic behavior with a real gap at Fermi level (E F) by the GGA and the mBJ approximations, whereas where using the GGA + U approach Ru 2 CrAl exhibit a near half metallic character with an indirect pseudogap. We also computed the elastic properties using where we found that this compound is mechanically stable. Moreover, we have studied the thermodynamic and thermoelectric properties for different temperatures and pressures. To our knowledge, these properties under study have not yet been measured or calculated; hence, our results serve as a prediction for future studies. The obtained results indicate that this ternary alloy is attractive for materials used in spintronic devices. [ABSTRACT FROM AUTHOR]

We used the density functional theory (DFT) based on full-potential linearized augmented plane wave (FP-LAPW) method implemented in WIEN2K code, to predict the structural, magnetic, electronic and elastic properties of the full-Heusler alloys Co 2 MB (M = V,Mn) and their MB-terminated (001) surfaces behavior. We showed that the studied alloys are more stable in the ferromagnetic order than the non-magnetic order. The calculated spin magnetic moments of Co 2 VB and Co 2 MnB were in good agreement with Slater-Pauling rule. The bulk of Co 2 VB was predicted to be a half-metallic ferromagnet with E g = 0. 63 eV, and the Fermi level lies in the middle of the indirect gap, and the electrons at E F were fully spin-polarized, unlike to Co 2 MnB which behaves as a metal. The half-metallicity of the bulk Co 2 VB was destroyed at (001) surface due to the symmetry reduction. The calculated elastic constants showed that compounds are stable and exhibit a ductile behaviour. The Young's modulus 3D representation showed that studied materials display a strong anisotropy. • DFT calculations are used to investigate of Cobalt-based full Heusler alloys. • Study of electronic and magnetic properties of Co 2 MB (M = V, Mn) using DFT + U approach. • The bulk Co 2 VB was predicted to be a half-metallic ferromagnet. • The calculated elastic constants confirmed a good stability of these compounds. [ABSTRACT FROM AUTHOR]

• All the V doped Hf 1-x V x O 2 (x = 0.25, 0.50, 0.75) alloys are found to have half-metallic character. • Spin up states are metallic and spin down semi-conducting. • Alloys exhibit magnetic moments 1.00, 2.00, and 3.00 μB. • The integer value of magnetic moment further confirms their half-metallic nature. • Furthermore, thermoelectric properties of these alloys have also been computed. • These alloys are suitable for magnetic, spintronic and thermoelectric applications. In this work, we have reported the first-principles calculations based on functional theory density on the structural, electronic, magnetic, bonding nature and thermoelectric properties of Hf 1-x V x O 2 alloys (x = 0, 0.25, 0.50, 0.75). For all the materials, the equilibrium structural parameters like that of lattice constant, bulk modulus and first pressure derivative of bulk modulus have been computed. The band profile and the density of states results demonstrate half-metallic nature for Hf 1-x V x O 2 alloys (x = 0.25, 0.50, 0.75). The calculated total magnetic moment was 1.0 μB/cell, 2.0 μB/cell, and 3.0 μB/cell, and the partial moment of V or local contribution is 1.08 μB, 1.85 μB, and 2.73 μB, respectively for Hf 1-x V x O 2 alloys (x = 0.25, 0.50, 0.75). The transport properties such as Seebeck coefficient, thermo power and thermal conductivity are found to have a great variation with V concentration. These alloys may find suitable applications in spintronic materials and in high temperature thermoelectric devices. [ABSTRACT FROM AUTHOR]

As one large family of intermetallic compounds, Heusler compounds offer a wide playground for novel materials design because of their wide range of compositions and tunable materials properties. In recent years, the high-throughput computational design has emerged as one efficient approach to search for target materials with desired properties thanks to the development of the automatic framework for materials discovery and open-access quantum materials database. In this article, we present a review of the current research progress of the high-throughput computational design of Heusler-based functional materials, including the selection of appropriate materials descriptors and common methods for evaluating materials stability, along with comprehensive lists of the predicated Heusler compounds with various types of target properties. We conclude the review with a discussion of the potential future research directions in the field. [ABSTRACT FROM AUTHOR]