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The present study focuses on the spin-dependent vibrational properties of HKUST-1, a metal–organic framework with potential applications in gas storage and separation. Employing density functional theory (DFT), we explore the consequences of spin couplings in the copper paddle wheels (as the secondary building units of HKUST-1) on the material's vibrational properties. By systematically screening the impact of the spin state on the phonon bands and densities of states in the various frequency regions, we identify asymmetric -COO- stretching vibrations as being most affected by different types of magnetic couplings. Notably, we also show that the DFT-derived insights can be quantitatively reproduced employing suitably parametrized, state-of-the-art machine-learned classical potentials with root-mean-square deviations from the DFT results between 3 cm−1 and 7 cm−1. This demonstrates the potential of machine-learned classical force fields for predicting the spin-dependent properties of complex materials, even when explicitly considering spins only for the generation of the reference data used in the force-field parametrization process. [ABSTRACT FROM AUTHOR]

Edge magnetism in zigzag nanoribbons of monolayer MoS 2 has been investigated with both density functional theory and a tight-binding plus Hubbard (TB+U) Hamiltonian. Both methods revealed that one band crossing the Fermi level is more strongly influenced by spin polarization than any other bands. This band originates from states localized on the sulfur edge of the nanoribbon. Its dispersion closely resembles that of the energy branch obtained in a linear chain of atoms with first-neighbor interaction. By exploiting this resemblance, a toy model has been designed to study the energetics of different spin configurations of the nanoribbon edge. [ABSTRACT FROM AUTHOR]

The Fe3GeTe2 monolayer, a ferromagnetic topological candidate with a high Curie temperature of 130 K, has recently garnered considerable interest. We investigated the impact of strain on the electronic, magnetic, and topological properties of the Fe3GeTe2 monolayer using density functional theory calculations. Our results showed that the Fe3GeTe2 monolayer was an itinerant ferromagnet with a high spin polarization of 69.93% and out-of-plane easy magnetization. Tensile strain had no profound impact on the anomalous Hall conductivity (AHC). However, when applying a compressive biaxial strain of −3%, the AHC at the Fermi level was dramatically enhanced to 1.62 e2/h, which is much larger than that of the bulk (0.7 e2/h) and bilayer (1.5 e2/h) material. The large AHC nearly coincided with the singularity of the energy bands near the M point. Our results highlight the potential of using strain engineering to control and optimize the properties of two-dimensional topological materials. [ABSTRACT FROM AUTHOR]

The structural, elastic, electronic, and magnetic properties of the CrCoSi, MnCoSi parent half-Heusler (HH) alloys, and their CrMnCo2Si2 derivative double half-Heusler (DHH) compound are studied, utilizing the augmented plane wave method, which is based on density functional theory and implemented in the WIEN2k code. The stability of HH structure of the CrCoSi and MnCoSi alloys has been checked for their non-magnetic and ferromagnetic phases, leading to that the latter phase of the type I arrangement is the most stable. The CrMnCo2Si2 DHH alloy, derivative from the found structural and magnetic ground states of CrCoSi and MnCoSi HH alloys, is constructed and investigated. This DDH as well as its CrCoSi parent HH are found to be resistant to deformation and can be classified as ductile materials, whereas the MnCoSi compound is brittle. By the gradient generalized approximation (GGA), the electronic structures of CrCoSi, MnCoSi, and CrMnCo2Si2compounds exhibit a metallic behavior in the spin-up channel and a semiconducting behavior in the spin-dn channel, with band gaps (half-metallic gaps) of 0.851(0.020), 0.852(0.021), and 0.531(0.002) eV, respectively. The half-metallicity of CrMnCo2Si2 DHH is retained with smaller (larger) band gap (half-metallic gap) of 0.38(0.106) eV than that of GGA, using GGA + U approximation. In addition, the total magnetic moments are found to be 1, 2, and 3 µB for CrCoSi, MnCoSi, and CrMnCo2Si2, respectively. Therefore, these alloys can be good candidates for spinitronic applications due to their half-metallicity. [ABSTRACT FROM AUTHOR]

Two-dimensional ferromagnetic (FM) half-metals are highly desirable for the development of multifunctional spintronic nano-devices due to their 100% spin polarization and possible interesting single-spin electronic states. Herein, using first-principles calculations based on density functional theory (DFT) with the Perdew–Burke–Ernzerhof (PBE) functional, we demonstrate that the MnNCl monolayer is a promising FM half-metal for spintronics. Specifically, we systematically investigated its mechanical, magnetic, and electronic properties. The results reveal that the MnNCl monolayer has superb mechanic, dynamic, and thermal (ab initio molecular dynamics (AIMD) simulation at 900 K) stability. More importantly, its intrinsic FM ground state has a large magnetic moment (6.16 μB), a large magnet anisotropy energy (184.5 μeV), an ultra-high Curie temperature (952 K), and a wide direct band gap (3.10 eV) in the spin-down channel. Furthermore, by applying biaxial strain, the MnNCl monolayer can still maintain its half-metallic properties and shows an enhancement of magnetic properties. These findings establish a promising new two-dimensional (2D) magnetic half-metal material, which should expand the library of 2D magnetic materials. [ABSTRACT FROM AUTHOR]

The electronic and magnetic properties of KCaN 2 /KCl(001) heterojunction have been studied within the framework of density functional theory using the full-potential linear augmented plane waves plus local orbital approach. There are two possible interface layers depending on the crystal structure of KCaN 2. The results demonstrate that the half-metallicity nature remains in both possible interfaces, i.e., KCl/KCa and KCl/NN. Spin polarization in both interfaces is complete, % 100, and the interface effects do not affect half-metallicity. The Schottky barrier height, band offsets, valence band maximum, and conduction band minimum to these interfaces were calculated and compared with the other half-metal/semiconductor heterostructures. • Half-metallicity preserves at the both KCl/KCa and KCl/NN interfaces. • There are two types of band alignment for different interfaces: staggered type for NN/KCl and straddling type for KCa/KCl interfaces. • Potential lineups are obtained, Δ V KCa/KCl =0 18 eV and Δ V NN/KCl =1.05 eV. [Display omitted] [ABSTRACT FROM AUTHOR]

The theoretical study of the thermoelectric properties of the FeV1-xMnxSb half-Heusler alloy (x = 0, 0.25, 0.5, 0.75, and 1) has been conducted using density functional theory. The aim of this research was to investigate the effect of Mn substitution on the FeVSb system in order to achieve a higher value of ZT. Our findings show that a system with an Mn doping concentration of x = 0:75 achieves the highest values of ZT ~ 0:90 for the spin-down states in the temperature range from 300 to 800 K, making it a promising candidate for future thermoelectric applications. On the other hand, the Mn substitution also triggers the magnetic moment formation and causes a large spin polarization at the Fermi level, leading the system to change from insulator to half-metallic. [ABSTRACT FROM AUTHOR]

First principles calculations are performed to investigate the thermodynamical stability, dynamical, mechanical, electronic and magnetic properties of CrTiCoZ (Z = Al/Si) novel quaternary Heusler alloys. A Y-type III atomic configuration is found to be the most stable structure for both compounds. The lattice constant values obtained using GGA-PBE approach are 5.9368 Å and 5.7853 Å for CrTiCoAl and CrTiCoSi, respectively. Using the value of elastic moduli for both the compounds, the computed Pugh's ratio value is 2.5 and 2.7 for CrTiCoAl and CrTiCoSi, respectively, which is higher than 1.75, indicating both the compounds are ductile in nature. The melting temperatures of both compounds are as high as 2142 K and 2420 K for CrTiCoAl and CrTiCoSi, respectively. The electronic structure calculations, using the GGA-PBE approach, show a half metallic behavior of CrTiCoAl. The spin-down channel exhibits a direct band gap of 0.15 eV, whereas the spin-up channel is metallic, making CrTiCoAl a half metallic ferromagnet with 100% spin polarization and an appreciable magnetic moment of −2 μB. However, CrTiCoSi is found to be semi-metallic in the spin-down channel and metallic in the spin-up channel, which leads to a spin polarization of 99.7% with a non-integer magnetic moment of −0.99 μB. The Curie temperature of CrTiCoAl is well above the room temperature (385 K), whereas that of CrTiCoSi is below the room temperature (203 K). Thus, CrTiCoAl is found to be more promising than CrTiCoSi as a spin injector in spintronic devices. [ABSTRACT FROM AUTHOR]

This study employs density functional theory (DFT) using Wien2k to comprehensively analyze the essential properties of two half-Heusler alloys, KCrSi and KCrGe. Our findings demonstrate that the ferromagnetic Type 2 configuration exhibits superior stability over non-magnetic and antiferromagnetic states for all KCrZ (Z = Si, Ge) alloys. These alloys exhibit complete spin polarization and half-metallic character, with calculated magnetic moments of 3 μB for both KCrSi and KCrGe. The Curie temperature (T C) is determined using the mean field approximation. Mechanical stability is assessed through second-order elastic constants (SOECs), and electronic properties are analyzed using local spin density approximation (LSDA), Perdew-Burke Generalized Gradient Approximation (PBE-GGA), and Tran-Blaha modified Becke-Johnson (TB-mBJ) schemes, confirming the retention of the half-metallic nature. The negative enthalpy of formation (ΔH) suggests material stability. The use of semi-classical Boltzmann theory, incorporated through the sophisticated scheme of BoltzTraP, explores transport coefficients. High pressures and temperature discrepancies in thermodynamics are considered by implementing the quasi-harmonic Debye approximation to illustrate stability. Finally, optical properties are summarized to assess the applicability of this alloy for optoelectronic applications. The overall characteristics of these particular alloys suggest potential applications in sustainable thermoelectric and optoelectronic features. • The stability in cubic structure is established with the help of structural optimization, and mechanical stability criteria. • The high Seeback coefficient and low thermal conductivity yield a high figure of merit ZT at 900 K. • The alloy has potential applications in thermoelectric technology and optoelectronic devices. [ABSTRACT FROM AUTHOR]

The spin polarization of carbon nanomaterials is crucial to design spintronic devices. In this paper, the first‐principles is used to study the electronic properties of two defect asymmetric structures, Cap‐(9, 0)‐Def [6, 6] and Cap‐(9, 0)‐Def [5, 6]. We found that the ground state of Cap‐(9, 0)‐Def [6, 6] is sextet and the ground state of Cap‐(9, 0)‐Def [5, 6] is quartet, and the former has a lower energy. In addition, compared with Cap‐(9, 0) CNTs, the C adatom on C30 causes spin polarization phenomenon and Cap‐(9, 0)‐Def [6, 6] has more spin electrons than Cap‐(9, 0)‐Def [5, 6] structure. Moreover, different adsorb defects reveal different electron accumulation. This finding shows that spin polarization of the asymmetric structure can be adjusted by introducing adatom defects. [ABSTRACT FROM AUTHOR]

The electronic, magnetic, and optical properties of PtcoBi half-Heusler compound [001] surfaces and its bulk state have been investigated in the framework of density functional theory using GGa approximation. the half-metallic behaviors of CoBiterm, CoPt-term and PtBi-term decrease with respect to its bulk state. the spin polarization at the Fermi level is 73.2% for the bulk state, and it is -64.4% and -64.1% for the coBi-term and PtBi-term, respectively while less polarization has been observed for the coPt-term. all terminations have given almost similar optical responses to light. Plasmon oscillations for the terminations occur in the range of 12.5 to 14.5 eV (21 to 22 eV) along xx (zz), and it occurs at 23 eV for the bulk state. the refractive index for the bulk and all three terminations is very high in the infrared and visible areas, meaning a very strong metallic trend in these compounds. the phenomenon of super-luminance occurs for the incident light with energy exceeding 5.5 eV for all three terminations, and it occurs in the range of 10 eV for the bulk mode. these terminations show transparent behavior after the energy of 10 eV. [ABSTRACT FROM AUTHOR]

Some nitrogen-based gases (NO, NO 2 , NH 3 and N 2 O) generate from the burning of fossil fuels and biomass, as well as from agricultural-related processes. They are directly related to both the deterioration of environment and human health. Research on two-dimensional materials as cores for sensing these types of harmful gases has attracted great interest; motivated by the fact that the interaction with those gases produces changes in their structural, electronic, magnetic and optical properties. In this work, investigation on the adsorption of those gases onto different blue phosphorene oxide species was carried out with the use of density functional theory, including Van der Waals interaction through KBM exchange-correlation functional. In the calculation, different positions and modes of molecule adsorption on the oxides were taken into account. The results obtained show that the interaction varies with both the nature of the molecule chemical composition and the oxide structure, resulting in different values of charge transfer, and leading to greater or lesser values of the adsorption energy of the gases. In some cases, spin polarization was observed, producing noticeable changes in the electronic structure and the optical spectrum of the nanosurfaces for each of the systems. The gases that produce the greatest change are NH 3 and NO, while those with the lowest optoelectronic responses on the different oxides are N 2 O and N 2 . The changes observed in the electronic structure as well as the short recovery time of gases would confirm the possibility of using these oxides for sensing applications, as it has been verified for other 2D nanomaterials. [ABSTRACT FROM AUTHOR]

In this study, the electronic behavior and mechanical properties of the ferromagnetic chalcospinel manganese-based selenide (AgMn2Se4) which crystallized in face centered cubic structure with space group ? and space number 227, were investigated. All ab initio calculations were carried out by Generalized Gradient Approximation (GGA) under spin polarization. For this composition, three different type magnetic orders were considered to detect the most stable magnetic character. For the given composition, the results of the computations indicate its ferromagnetic nature since this compound has a lower ground state energy in this magnetic order than in other magnetic phases. After determining the most energetically stable magnetic phase, the electronic behavior in this magnetic arrangement was examined. The observed electronic band structure under spin polarization of this compound shows that this selenide system is almost half-metallic material due to having small band gap (Eg = 0.09 eV) in the minority spin state. In addition, the mechanical stability was determined with the help of elastic constants which were also employed to determine the mechanical characteristics of this compound. [ABSTRACT FROM AUTHOR]

First principles electronic structural calculation of full Heusler alloys Ir2YSi (Y= Sc to Ni) in the L21 (Cu2MnAl) and Xa (Hg2CuTi) structures have been studied using full-potential linearized augmented plane wave method (FP-LAPW) based on density functional theory (DFT). From the total energy calculations, it has been observed that all these alloys are stable in L21 structure than Xa structure and also it is found that the alloys Ir2YSi (Y =V to Co) are ferromagnetically stable whereas the Ir2YSi (Y = Sc, Ti, and Ni) alloys are non-magnetic in their stable L21 structure. Spin polarized band structure calculations reveal that in Ir2YSi (Y= V to Co) alloys there is spin splitting of energy states around the Fermi level (EF) indicating ferromagnetism and moreover in Ir2YSi (Y = V, Cr, and Mn) alloys majority electrons have metallic behavior while minority electrons have semiconducting nature exhibiting half metallic ferromagnetic (HMF) nature. HMF property in Ir2YSi (Y = V, Cr, and Mn) alloys have been further confirmed from the integer total magnetic moment value of 3.0 µB, 4.0 µB and 5.0 µB per formula unit respectively. Spin polarization mainly arises from the interaction between 3d electrons of V/Cr/Mn atom and 5d electrons of Ir atom. This strong d-d hybridization between the transition atoms like Ir and V/Cr/Mn composing Heusler alloys is essential for the formation of gap at the EF between the valence and conduction bands. Our results show that Ir2YSi (Y= V, Cr, and Mn) will be suitable for ferromagnetic and spintronics applications. [ABSTRACT FROM AUTHOR]

Inspired by the recent progress on the intrinsic two-dimensional (2D) ferromagnetism, we studied three potential 2D magnets (Mn3X4; X = Te, Se, S) by performing the first-principles calculation based on the density functional theory and Monte Carlo simulations. We predicted intrinsic ferromagnetism in monolayers Mn3Te4 and Mn3Se4, which are half-metallic with 100% spin polarization at the Fermi level. The half-metal band gap of monolayers Mn3Te4 and Mn3Se4 is 0.62 and 0.83 eV, respectively. More importantly, the Curie temperatures of Mn3Te4 and Mn3Se4 were estimated to be above the room temperature by performing the Monte Carlo simulations, suggesting ferromagnetic ordering at room temperature. Additionally, we calculated the phonon spectrum, elastic modulus, and performed the ab initio molecular dynamics simulation which proves that monolayers Mn3Te4 and Mn3Se4 are thermally, dynamically and mechanically stable. Plus, mechanical stripping method was proven to be the feasible way to obtain single-layer Mn3X4. [ABSTRACT FROM AUTHOR]

The half-metallic, mechanical, and transport properties of the quaternary Heusler compound of PdZrTiAl is discussed under hydrostatic pressures in the range of -11.4 GPa to 18.4 GPa in the framework of the density functional theory (DFT) and Boltzmann quasi-classical theory using the generalization gradient approximation (GGA). By applying the stress, the band gap in the minor spin increases so that the lowest band is obtained 0.25 eV at the pressure of -11.4 GPa while the maximum gap is calculated 0.9 eV at the pressure of 18.4 GPa. In all positive and negative pressures, the PdZrTiAl composition exhibits a half-metallic behavior 100% spin polarization at the Fermi level. It is also found that applying stress increases the Seebeck coefficient in both spin directions. In the minority spin, the n-type PdZrTiAl, the power factor (PF) for all the cases is greater in the equilibrium state than the strain and stress conditions whereas in the majority spin, the PF value of the stress state is greater than the other two. The non-dimensional figure of merit (ZT) is significant and is about one in spin down in the room temperature for the all pressure states that it remains on this value by applying pressure. The obtained elastic constants indicate that the PdZrTiAl crystalline structure has a mechanical stability. Based on the Yong (E), Bulk (B) and shear (G) modulus and Poisson (n) ratio, the brittle-ductile behavior of this compound has been investigated under pressure. The results indicate that PdZrTiAl has a ductile nature and it is a stiffness compound in which elastic and mechanical instability increases by applying strain. [ABSTRACT FROM AUTHOR]

We have performed a study of the structural, elastic, electronic, and magnetic properties of ZnCrO2 and ZnMnO2 chalcopyrite, using the Full-potential linearized augmented wave method (FP-LAPW), as part of the density functional theory (DFT). We have treated the exchange and correlation energy with the generalized gradient approximation (GGA-PBEsol) and the Tran-Blaha modified Becke-Johnson (TB-mBJ) meta-GGA. We have obtained new predictions for elastic properties. We have shown that these compounds are half-metals, and a spin polarization of 100% at the Fermi level. From these new results, we have predicted that these compounds are suitable in spintronic and optoelectronic applications. [ABSTRACT FROM AUTHOR]

[Display omitted] The quaternary Heusler alloys with composition LiAEFeSb have been studied in this manuscript (AE = Alkaline Earth elements Be, Mg, Ca, Sr and Ba) for their potential applications in spintronics. All the investigations have been performed by employing density functional theory. A systematic comparison of results obtained within local density approximation (LDA) and the generalized gradient approximation (GGA) done. Our calculations reveal that all the studied alloys have lowest energy in type-I arrangement of basis and exhibit interesting electronic and magnetic properties. All the alloys exhibit a stable ferromagnetic ground state. Fixed spin moment calculations rule out existence of any other local magnetic minima. The phonon dispersions show that all the alloys except LiBeFeSb are dynamically stable. Notably, LiSrFeSb and LiBaFeSb exhibit half-metallic electronic band structure and 100 % spin polarization making them suitable choice for promising spintronic applications such as spin filter and detectors. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) calculations including spin polarization were performed to obtain the energies for all end-member configurations of the μ phase, which were used to evaluate the Gibbs energies of the μ phase. The Co–W system was thermodynamically re-assessed in the present work. The present calculated phase diagram fits well with the experimental data. Applying the DFT results was essential for giving a better description of the μ phase. [ABSTRACT FROM AUTHOR]

In this work, we have used the first-principle calculations approach based on spin-polarized density functional theory, and predicted the half-metallic behavior of In1-xMnxSb alloys (x = 0:25, 0.50, 0.75). The structural, electronic and magnetic properties of these ternary cubic crystals have been investigated. The electronic exchangecorrelation energy has been characterized by the generalized gradient approximation with the WC functional improved by the Tran-Blaha modified Becke-Johnson exchange potential approximation. The calculated formation energy indicates that In1-xMnxSb compounds (at all compositions) are thermodynamically stable, and can be synthesized. Our calculated structural parameters are in good accordance with the available theoretical and experimental data. The ternary alloys In1-xMnxSb are half-metallic ferromagnets with a spin polarization at the Fermi level of 100%. Our investigation shows an antiferromagnetic interaction between Mn-Sb and Mn-In, the total magnetic moment is equal to 4:00 μB for all studied structures. These materials are half-metallic ferromagnets, and thus may be potential candidates for spintronics applications. [ABSTRACT FROM AUTHOR]

Abstract We calculate the temperature dependent spin-polarized transport properties of ferromagnetic vanadium ditelluride (VTe 2) single layer by using density functional theory (DFT) along with non-equilibrium Green's function (NEGF) formulation. The spin-dependent current and transmission spectrum are calculated to explain the spin filtration effect based on temperature and excellent spin Seebeck effect. A high value of Spin polarisation efficiency ∼100% is achieved at a lower value of temperature difference range. Due to the high-temperature difference between the left electrode (T L) and right electrode (T R) lower Spin polarisation efficiency is obtained. A thermal giant magneto resistance of ∼1.5 × 103% is obtained and it increases with increase in temperature difference between the left and right electrode (ΔT), and it also depends on T L. The excellent characteristics such as high MR and perfect spin polarisation makes VTe 2 a prominent material for spin caloritronic applications. Highlights • Temperature dependent spin Seebeck and spin filtration effect is observed in VTe 2. • Thermal GMR increases with increase in electrode temperature difference (ΔT). • Higher spin polarisation efficiency at lower ΔT and vice-versa. [ABSTRACT FROM AUTHOR]

Herein, structural, optical, magnetic, electronic, and thermoelectric (TE) characteristics of cubic spinels Ln 2 MnSe 4 (Ln = Yb, Lu) are examined by DFT + U. Enthalpy of formation (ΔH f) for both spinels are negative (−3.189 and −2.251 eV for Yb 2 MnSe 4 and Lu 2 MnSe 4 , correspondingly), which supports thermodynamical stability for both spinels. Spin dependent band structures and density of state (DOS) disclose the half metallic and magnetic semiconducting nature for both Ln 2 MnSe 4 (Ln = Yb, Lu) spinels, respectively, with direct bandgaps of 1.44 eV in spin up and metallic in spin down for Yb 2 MnSe 4 whereas Lu 2 MnSe 4 has 0.5/1.5 eV in spin up/down channel. Optical response of Ln 2 MnSe 4 (Ln = Yb, Lu) spinels is also determined. At 0 eV, the computed results of refractive index n (ω) for Yb 2 MnSe 4 /Lu 2 MnSe 4 are 12.0/2.89, respectively. For Yb 2 MnSe 4 and Lu 2 MnSe 4 peak value of σ(ω) are calculated as 7813.08 at 7.03 eV and 7532.71 (1/Ωcm) at 6.47 eV, respectively. To assess the temperature dependent transport behavior of both compounds, thermoelectric (TE) characteristics including power factor (PF), Seebeck coefficient (S), thermal conductivity (k/τ), electrical conductivity (σ/τ) and figure of merit (ZT) are determined. Maximum ZT values for Yb 2 MnSe 4 and Lu 2 MnSe 4 are 0.18 and 0.79 at 800 K, correspondingly. Results show that Yb 2 MnSe 4 is suitable contender spintronics due to 100% spin polarization at Fermi level whereas Lu 2 MnSe 4 is useful addition to magnetic semiconductor family having potential applications in opto-electronic and TE devices. Spin dependent band structures and density of state (DOS) disclose the half metallic and magnetic semiconducting nature for both Ln 2 MnSe 4 (Ln = Yb, Lu) spinels, respectively, with direct bandgaps of 1.44 eV in spin up and metallic in spin down for Yb 2 MnSe 4 whereas Lu 2 MnSe 4 has 0.5/1.5 eV in spin up/down channel. Optical response of Ln 2 MnSe 4 (Ln = Yb, Lu) spinels is also determined. At 0 eV, the computed results of refractive index n (ω) for Yb 2 MnSe 4 /Lu 2 MnSe 4 are 12.0/2.89, respectively. For Yb 2 MnSe 4 and Lu 2 MnSe 4 peak value of σ(ω) are calculated as 7813.08 at 7.03 eV and 7532.71 (1/Ωcm) at 6.47 eV, respectively. Maximum ZT values for Yb 2 MnSe 4 and Lu 2 MnSe 4 are 0.18 and 0.79 at 800 K, correspondingly. Results show that Yb 2 MnSe 4 is suitable contender spintronics due to 100% spin polarization at Fermi level whereas Lu 2 MnSe 4 is useful addition to magnetic semiconductor family having potential applications in opto-electronic and TE devices. [Display omitted] • ΔH f confirm the thermal stability for both compounds. • Yb 2 MnSe 4 /Lu 2 MnSe 4 are half metallic and magnetic semiconducting nature, respectively. • Maximum ZT values for Yb 2 MnSe 4 /Lu 2 MnSe 4 are 0.18/0.79, correspondingly. • Both spinels are applicants for opto-electronic and TE applications. [ABSTRACT FROM AUTHOR]

In the context of characterizing nitrogen-poor carbonitrides for different applications, identification of an unusual onset of spin polarization of N(p) states has been shown. A full saturation up to 3 μB is demonstrated in extended two-dimensional carbon networks of NC6 and NC12 hexagonal structures refined based on density functional theory calculations. From establishing the energy-volume equations of states in both compounds assuming spin-degenerate (non-spin-polarized) and spin-polarized configurations, the ground state is identified as ferromagnetic. The variation of magnetization with volume points to strongly ferromagnetic behavior. [ABSTRACT FROM AUTHOR]

Searching experimental feasible two-dimensional (2D) ferromagnetic crystals with room-temperature magnetic order and high spin-polarization is one key for the development of next-generation spintronic devices. Inspired by the recent experimental achievement for the synthesis of Janus MoSSe monolayer with out-of-plane symmetry, here, by ab initio calculation, we demonstrate this feasibility with the discovery of intrinsic 2D ferromagnetic Janus TMDs monolayer (TMXX′, TM = V, Cr and Mn; X, X′ = S, Se and Te, X ≠ X′) with large spin-polarization and high Curie temperature. Particularly, the MnSSe monolayer show half-metal with 100% spin polarization and wide half-metallic gap. A Curie temperature as high as 400 K has been found for VSSe materials. The formation energy calculation for Janus TMDs can be comparable with the TMDs monolayer. The dynamical stability for these 2D crystals also have been confirmed by phonon spectrum calculation. Our study presents a new class of 2D magnetic materials for future spintronics and valleytronics. [ABSTRACT FROM AUTHOR]

Using the first-principles periodic boundary density functional theory along with the Grimme function, this study investigated the vacancy formation in the neck area of a 3-D pillared graphene structure. Three different possible configurations of the monovacancy defect formation were studied on a 3-D pillared graphene in order to explore the role of the monovacancy defect in the structural, electronic, and magnetic properties of each configuration. The density of state (DOS), projected DOS and spin polarization of the defected structures were calculated in order to determine which monovacancy site could have a significant impact on the magnetization of the 3-D pillared graphene. The obtained results at the GGA/revPBE level with a DZP basis set revealed that the influence of changing the position of the monovacancy defects from the graphene sheet to the nanotube part of the 3-D pillared graphene could give rise to greater magnetization. In particular, the monovacancy defects on the graphene (sheet) and nanotube (pillar) parts of the 3-D pillared graphene yielded less magnetization and greater magnetization, respectively. Moreover, the simulation results indicated that the px and pz orbitals had a substantial contribution to the spin polarization in these structures. [ABSTRACT FROM AUTHOR]

Structural, electronic and magnetic properties of the Heusler alloy Mn2VIn have been investigated using the density functional theory and experimental techniques. Unlike many other Heusler compounds, Mn2VIn is not predicted to be half-metallic at the optimized lattice constant, but is highly spin polarized at a slightly lower lattice constant. It however exhibits ferrimagnetic coupling between the Mn and V sublattices, as expected of Mn-based Heuslers. We have, then, synthesized the compound by arc melting and studied magnetic properties that are of interest fundamentally and for technological applications. The structural properties were determined using X-ray diffraction, revealing the presence of cubic and tetragonal phases in the sample. The chemical composition was determined using energy-dispersive X-ray spectroscopy together with the scanning electron microscope, and the magnetic properties were investigated by superconducting quantum interference device magnetometry. The alloy exhibits superparamagnetic spin blocking with a blocking temperature TB of 40 K. [ABSTRACT FROM PUBLISHER]

The electronic and magnetic properties of the half-metallic ferromagnet Fe2Si under (0001) strain have been evaluated by the first-principles density functional theory method. The spin-up band structure shows that bulk Fe2Si has metallic character, whereas the spin-down band structure shows that bulk Fe2Si is an S-L indirect band gap of 0.518 eV in the vicinity of Fermi surface. Indirect-to-direct band gaps and an unstable-to-stable transition are observed in bulk Fe2Si as strain is applied. In the range −11% to 11% (excluding zero strain), bulk Fe2Si has stable half-metallic ferromagnetism, the spin polarization at the Fermi surface is 100%, and the magnetic moment of the Fe2Si unit cell is 4.0 μB. The density distribution shows that the spin states of bulk Fe2Si mainly come from the Fe1-3d and Fe3-3d states, indicating that bulk Fe2Si has spin-polarized ferromagnetism. The half-metallic ferromagnetism of bulk Fe2Si is mainly caused by d–d exchange and p–d hybridization, which are not sensitive to strain. It is very important to investigate the effect of changes in the lattice constant on the half-metallic ferromagnetic properties of bulk Fe2Si. [ABSTRACT FROM AUTHOR]

Based on the relativistic spin-polarized density functional theory calculations we investigate the crystal structure, electronic and magnetic properties of a family MnPn 2 Ch 4 compounds, where pnictogen metal atoms ( Pn ) are Sb and Bi; chalcogens ( Ch ) are Se, Te. We show that in the series the compounds of this family with heavier elements prefer to adopt rhombohedral crystal structure composed of weakly bonded septuple monoatomic layers while those with lighter elements tend to be in the monoclinic structure. Irrespective of the crystal structure all compounds of the MnPn 2 Ch 4 series demonstrate a weak energy gain (of a few meV per formula unit or even smaller than meV) for antiferromagnetic (AFM) coupling for magnetic moments on Mn atoms with respect to their ferromagnetic (FM) state. For rhombohedral structures the interlayer AFM coupling is preferable while in monoclinic phases intralayer AFM configuration with ferromagnetic ordering along the Mn chain and antiferromagnetic ordering between the chains has a minimum energy. Over the series the monoclinic compounds are characterized by substantially wider bandgap than compounds with rhombohedral structure. [ABSTRACT FROM AUTHOR]

The properties of Re-doped single-layer MoS 2 have been investigated by density functional theory (DFT). Four doping configurations are considered, and all of them show large spin polarization. We ascribe the spin polarization of these systems to the single occupation of split 5d orbitals under different crystal fields and the charge transfer from Re atom to single-layer MoS 2 . Furthermore, our results show that ferromagnetic ground states are favored in these doped systems when different spin orders are considered. These results would be helpful for future MoS 2 -based spintronic devices. [ABSTRACT FROM AUTHOR]

The electronic structure and magnetic property of Mn 2 Co 1−x Cr x Al (x = 0.25, 0.5, 0.75) have been investigated based on density functional theory calculations. The results indicate that both Mn 2 Co 0.75 Cr 0.25 Al and Mn 2 Co 0.25 Cr 0.75 Al are half metals with a half-metallic gap of 0.07 eV and 0.08 eV, respectively. In addition, Mn 2 Co 0.75 Cr 0.25 Al can maintain the half-metallicity even when the crystal structure is disordered, while the half-metallicity of Mn 2 Co 0.25 Cr 0.75 Al is destroyed once the disorder appears. For Mn 2 Co 0.75 Cr 0.25 Al, the half-metallic gap of the Cr-Co disordered structure is 0.14 eV, suggesting a great potential to be a good candidate for spintronic application. [ABSTRACT FROM AUTHOR]

The structure of the interfaces and the mechanisms of induced spin polarization of 1D infinite and finite narrow graphene- and h-BN zigzag nanoribbons placed on a SrO-terminated La1-xSrxMnO3 (LSMO) (001) surface were studied using density functional theory (DFT) electronic structure calculations. It was found that the π-conjugated nanofragments are bonded to the LSMO(001) surface by weak disperse interactions. The types of coordination of the fragments, the strength of bonding, and the rate of spin polarization depend upon the nature of the fragments. Infinite and finite graphene narrow zigzag nanoribbons are characterized by the lift of the spin degeneracy and strong spin polarization caused by interface-induced structural asymmetry and oxygen-mediated indirect exchange interactions with Mn ions of LSMO support. Spin polarization changes the semiconducting nature of infinite graphene nanoribbons to half-metallic state with visible spin-up density of states at the Fermi level. The h-BN nanoribbon binding energy is weaker than graphene nanoribbon ones with noticeably shorter interlayer distance. The asymmetry effect and indirect exchange interactions cause spin polarization of h-BN nanoribbon as well with formation of embedded states inside the band gap. The results show a possibility to use one-atom thick nanofragments to design LSMO-based heterostructures for spintronic nanodevices with h-BN as an inert spacer to develop different potential barriers. [ABSTRACT FROM AUTHOR]

[Display omitted] • The N -doped coralline Co 9 S 8−x N x catalyst possessed filamentous porous structures. • ∼100 % degradation efficiency of AMT was achieved in 120 min. • Electrons redistribution and charge transfer mechanisms of Co 9 S 8−x N x were revealed. Improving the recalcitrant emergent contaminant removal in electron-Fenton (EF) has been one of the focal problems. Here, a N -doped coralline Co 9 S 8−x N x catalyst was synthesized with high electronegativity and strong spin polarization for promoting the H 2 O 2 generation efficiency and Amitriptyline (AMT) removal. After doping nitrogen, catalytic performance of Co 9 S 8−x N x has increased ∼10 % on AMT decay and the treatment time was shortened ∼40 min. Co 9 S 8−x N x induced 2-electron oxygen reduction reaction (ORR) mechanism has also been investigated. According to electronic structure analysis, electrons surrounding the cobalt atoms were redistributed and the π* orbitals of *O 2 were occupied asymmetrically forcing *O 2 to be of radical nature active for hydrogenation, which significantly reduced required absorption energy in the rate-determining step (RDS). This work clarifies the mediate role of N -doped activating delocalized electron of adjacent atoms on the surface of Co 9 S 8−x N x and also gives new insights into the rational design of catalyst for refractory pollutant degradation in wastewater. [ABSTRACT FROM AUTHOR]

Using spin-polarized density functional theory calculations, we demonstrated that carbon doped boron nitride nanowire (C-doped BNNW) has diverse electronic and magnetic properties depending on position of carbon atoms and their percentages. Our results show that only when one carbon atom is situated on the edge of the nanowire, C-doped BNNW is transformed into half-metal. The calculated electronic structure of the C-doped BNNW suggests that doping carbon can induce localized edge states around the Fermi level, and the interaction among localized edge states leads to semiconductor to half-metal transition. Overall, the bond reconstruction causes of appearance of different electronic behavior such as semiconducting, half-metallicity, nonmagnetic metallic, and ferromagnetic metallic characters. The formation energy of the system shows that when a C atom is doped on surface boron site, system is more stable than the other positions of carbon impurity. Our calculations show that C-doped BNNW may offer unique opportunities for developing nanoscale spintronic materials. [ABSTRACT FROM AUTHOR]

The paper presents the results of the plane wave density functional theory calculations of newly predicted Y2FeSi full-Heusler alloy with optimized lattice constants. We have explored two most likely structures (AlCu2Mn and CuHg2Ti prototypes) with different atomic arrangements and including collinear magnetic ordering. The results show that the classic L21 structure is more favourable in terms of energy than the second one studied in this work. Moreover, for both crystalline structures ferromagnetic arrangement is more favourable, although in the second structure the difference in energy between ferromagnetic and nonmagnetic state is small. Study did not revealed band gap in any spin channel, yet the spin polarization in majority channel at the Fermi level is significant (σ = 83%). The calculated structural lattice a parameter for the energetically lowest structure is a = 13:0996 a0. For the lattice constant range of 12.2 to 13.2 a0 the total magnetic moment varies significantly from 0.86 μB to 1.74 μB per formula unit. [ABSTRACT FROM AUTHOR]

In this paper, spin and non-spin polarization (SP, NSP) are performed to study structural properties and bond hardness of FeB ( x = 1, 2, 3) compounds using density functional theory (DFT) within generalized gradient approximation (GGA) to evaluate the effect of spin polarization on these properties. The non-spin-polarization results show that the non-magnetic state (NM) is less stable thermodynamically for FeB compounds than spin-polarization by the calculated cohesive energy and formation enthalpy. Spin-polarization calculations show that ferromagnetic state (FM) is stable for FeB structures and carry magnetic moment of 1.12, 1.83 and 2.03 μB in FeB, FeB and FeB, respectively. The calculated lattice parameters, bulk modulus and magnetic moments agree well with experimental and other theoretical results. Significant differences in volume and in bulk modulus were found between the ferromagnetic and non-magnetic cases, i.e., 6.8, 32.8%, respectively. We predict the critical pressure between ferromagnetic and non-magnetic phases. The model for hardness calculation using Mulliken population coupled to semi-empirical hardness theory proved effective in hardness prediction for the metal borides which agree well with the experimental values. These results would help to gain insight into the spin-polarized effect on the structural and bond hardness. [ABSTRACT FROM AUTHOR]

Spin-polarized density functional theory calculations have been performed to investigate the preferential mechanism of CH x ( x = 1–3) formation in Fischer-Tropsch synthesis on only the hexahedron Co( 10 1 ¯ 0 )-A and Co( 10     1 ¯ 0 ) surfaces. Our results show that CO hydrogenation to CHO is favored compared to CO direct dissociation and hydrogenation to COH on these two surfaces. Starting from C and CHO, we further seek out the optimal pathways of CH x formation, suggesting that CH x is mainly formed through H-assisted CO dissociation pathways on Co( 10 1 ¯ 0 )-A surface, in which CH is form via CHO dissociation, CH 2 and CH 3 are formed through CH 2 O with the direct and H-assisted dissociation, respectively; meanwhile, CH 2 hydrogenation also contributes to CH 3 formation; CH 2 and CH 3 are the surface abundant species on Co( 10 1 ¯ 0 )-A surface. However, on Co( 10 1 ¯ 1 ) surface, CH x species is formed through CO direct dissociation into C, followed by C successive hydrogenation, C and CH are the surface abundant species. Therefore, Co surface structure can affect the preferential formation pathways and the dominant existence form of CH x species. Moreover, CH 3 OH formation cannot compete with CH x formation on Co( 10 1 ¯ 0 )-A and Co( 10 1 ¯ 1 ) surfaces, considering both surfaces covering 63% of the total surface area exposed of hexahedron Co surfaces, which depends on the reaction conditions, particle size, catalyst support, carbon deposition and many other factors, the contribution to the overall CH x sources from Co( 10 1 ¯ 0 )-A and Co( 10 1 ¯ 1 ) surfaces even surpasses that of other hexahedron Co surfaces under the certain realistic conditions. As a result, the hexahedron Co surfaces exhibit high catalytic selectivity for CH x formation, and provide more CH x sources to participate into the F-T synthesis. [ABSTRACT FROM AUTHOR]

Based on first-principles spin-polarized density functional theory calculations, the electronic structures, and magnetic properties of Cu and Zn-doped BiFeO 3 are investigated. The calculated formation energies show that Cu prefers to occupy Fe site, while the Zn prefer to occupy Bi site. All the doped BiFeO 3 systems turn out to be favorable for G-type antiferromagnetic arrangement. The substitution of Cu and Zn for Fe produces a magnetic moment of 3.0 and 4.0 μ B per dopant, respectively. The net magnetic moments are from the broken symmetry of the AFM spin ordering network. For the substitution of Cu and Zn for Bi, the net magnetic moment originates from Cu/Zn itself and hole introduced by Cu/Zn. Two-Cu/Zn-doped cases show various magnetic behaves. If O vacancy is far away from dopants, the O vacancies don't affect the net magnetic moment of the substitution of Cu and Zn for Fe, but have notable effect for Bi site doping. The O vacancies result in metallicity in all doped cases. Our study demonstrates that the nonmagnetic Cu and Zn doping will lead to the diversity and complexity of magnetic properties depending on doping sites, distance between dopants, intrinsic defect, and so on, which could be responsible for the observed various magnetic behaviors in Cu/Zn-doped BiFeO 3 samples. [ABSTRACT FROM AUTHOR]

Spin polarized density functional theory calculation combined with periodic slabs were employed to reveal the elemental mercury (Hg 0 ) adsorption mechanism on Co 3 O 4 (1 1 0) surface. The adsorption energies and possible adsorption sites were investigated. To understand the adsorption interaction more directly, the electronic structural changes of before and after adsorption were compared. The hybridization of orbitals was studied by the partial density of states (PDOS) analysis. In addition, the temperature effects toward equilibrium constants of Hg 0 –Co 3 O 4 system were taken into consideration. The results manifested that the interaction between Hg 0 and Co 3 O 4 (1 1 0) surface is chemisorption with −74.037 kJ/mol. Co 3+ sites, the highest oxidation state of Co atoms, are crucial in this process which can accept the electrons after Hg oxidation. The redundant electrons transfer to O and other Co atoms nearby. PDOS analysis indicates the hybridization of s orbitals (Hg 0 ) and p, d orbitals (Co atom). And d orbitals of Hg interacts with s, p orbitals of Co atom strongly. The trends of equilibrium constants suggest that Hg 0 adsorption on Co 3 O 4 (1 1 0) surface is favorable at low temperature. [ABSTRACT FROM AUTHOR]

The electronic structures of ε-phase of solid oxygen (O2)4 are studied within the framework of densityfunctional theory. The intriguing molecule has been known to have magnetic properties at room temperature by applying pressure. Nevertheless, until now there was no evidence of band structure studied in the antiferromagnetic behaviour of (O2)4. We report a comparison study for spin and non-spin polarization orbital which suggests that this ferromagnetic configuration of (O2)4 could not be seen experimentally, and antiferromagnetic configuration of (O2)4 was seen at higher pressure of about 10 GPa. The antiferromagnetic state transforms into the superconducting state as the sample temperature decreases. The results can serve as a useful approximation in studying general features of the electronic structure. The (O2)4 clusters are reported in the Raman study, having significant absorption at 1516 cm-1 below infrared region. [ABSTRACT FROM AUTHOR]

In this work, DFT calculations were conducted to understand the interactions of two luminescent complexes series, named [Ln(cin) 3 (H 2 O) 3 ]·Hcin and the [Ln 2 (cin) 6 (bpy) 2 ] (where cin = hydrocinnamate anion and bpy = 2,2′-bipyridine). For the reduction of the computational cost in the geometry optimization calculations, the PBE-D2 and the GGA + U methodologies were tested, even as the 4f electrons treatment, in the core and in the valence shell of the lanthanide metals. As a result of the electronic structure calculations, the lattice parameters of these complexes was obtained and corroborated by a comparison between the simulated and experimental diffractograms. The projected density of states and the charge density analysis were made for a better understanding of the electronic structure and the stabilization of these complexes, like the importance of some ligands and the difference of the interaction between the rare-earth metals and the ligands. It could be concluded that there is no need to compute the spin polarization and to include the hubbard correction in order to conduct a structural analysis of these rare-earth metal complexes. The electronic density maps show that the structures are mainly stabilized by charge transfer between the ligands and the rare-earth cations. This result also corroborates the geometry optimizations performed with the DFT-D2 method, which indicate that the computation of the Van der Waals forces are negligible. [ABSTRACT FROM AUTHOR]

We calculate the electronic structure and magnetism of monolayer phosphorene doped by nonmagnetic atoms. O, S and Se impurities can induce the magnetic moment. O doping makes it become a spin-gapless semiconductor, but S and Se doping induces a half-metallic characteristic. The p orbital of dopant has a strong hybridization with P around impurities, which induces spin splitting of P and impurities. C induces a metallic character. B acts as n -type dopant and F results in p -type dopant. The magnetism of phosphorene doped by two O atoms strongly depends on the doping sites and distance between two O atoms. [ABSTRACT FROM AUTHOR]

Spin-polarized density functional theory computations have been performed to investigate n CO + m H 2 co-adsorption and mutual interaction on the Fe(1 1 0) and Fe(1 1 1) surfaces. It is found that CO pre-coverage affects hydrogen adsorption strongly, while H pre-coverage hardly affects CO adsorption. It is possible to have CO + H 2 co-adsorption on Fe(1 1 0), while very strong preference of CO pre-coverage on Fe(1 1 1) has been found. On Fe(1 1 1), it is also found that each CO molecule blocks on average 2H adsorption sites at all CO pre-coverage. All these findings are consistent with available experimental results. Compared with CO/H 2 ratios in gas phase, CO/H 2 surface ratios are very different and much more sensitive to temperature than pressure. Our results provide the basis for exploring the mechanisms of iron-catalyzed conversion of synthesis gas. [ABSTRACT FROM AUTHOR]

Recently, p -type conduction of InN doped by alkaline earth was reported in experiments. However, the magnetic property of the doped systems has not been studied. We systematically investigate the magnetic property of alkaline-earth doped InN by density-functional theory. Our results reveal that the ground state of the doped system transits from nonmagnetic state to spin-polarized state, and the holes introduced into the valence band become more localized as the defect ranges from Be to Ba. As a result, strong half-metallic ferromagnetism emerges for Sr- or Ba-doped InN. Our calculations reveal that the formation energy of defect is much lower for nitrogen-rich condition, under which the doped system can be favorably synthesized. [ABSTRACT FROM AUTHOR]

We have investigated spin polarization in bulk and thin films of nitrogen intercalated Cu 3 N (Cu 3 N 2 ) structure by means of first-principles calculations based on Kohn–Sham density functional theory and ultrasoft pseudopotentials technique. The results show that after an accurate structural relaxation of the system, magnetism in the bulk structure vanishes. This effect is due to the migration of the intercalated nitrogen atom from the body center of the cell to the vicinity of the cell faces. In addition, similar study for the thin films of 5, 7, 9 and 11 monolayers thickness shows that initial relaxation of structures with 7 and 11 monolayers show a net magnetic moment of 2.6 μ B . By an extended survey of the energy surfaces, the film with 7 monolayers loses its magnetic moment, but the film with 11 monolayers maintains its magnetic moment. Density of states plot demonstrates that the spin polarization in the 11 monolayers thin film is due to the polarization of 2 p orbital of middlemost nitrogen atom. [ABSTRACT FROM AUTHOR]

Abstract: The electronic structure and magnetic properties of (Al, Fe) codoped 4H-SiC have been systematically studied by first principles calculations. The most energetically favorable structures in fourteen possible atomic geometries with deferent Al–Fe bondings were determined. Al dopant alone does not introduce any spin-polarization, whereas (Al, Fe) codoped 4H-SiC can induce spin-polarization. The local magnetic moment in (Al, Fe) codoped 4H-SiC is mainly contributed by Fe-3d orbitals. Ferromagnetism order is the preferred ground state and the interaction between the local moments is activated through holes induced by Fe doping via a Fe:3d-C:2p-Fe:3d coupling chain in short Fe–Fe separations. [Copyright &y& Elsevier]

In this work we present a theoretical study of the effect of disorder on spin polarisation at the Fermi level, and the disorder formation energies for Co2FexMn1-xSi (CFMS) alloys. The electronic calculations are based on density functional theory with a Hubbard U term. Chemical disorders studied consist of swapping Co with Fe/Mn and Co with Si; in all cases we found these are detrimental for spin polarisation, i.e., the spin polarisation not only decreases in magnitude, but also can change sign depending on the particular disorder. Formation energy calculation shows that Co-Si disorder has higher energies of formation in CFMS compared to Co2MnSi and Co2FeSi, with maximum values occurring for x in the range 0.5-0.75. Cross-sectional structural studies of reference Co2MnSi, Co2Fe0.5Mn0.5Si, and Co2FeSi by Z-contrast scanning transmission electron microscopy are in qualitative agreement with total energy calculations of the disordered structures. [ABSTRACT FROM AUTHOR]

The effect of magnetic field on the structure properties of hot spin polarized strange quark stars has been investigated. For this purpose, we use the MIT bag model with a density-dependent bag constant to calculate the thermodynamic properties of spin polarized strange quark matter such as energy and equation of state. We see that the energy and equation of state of strange quark matter changes significantly in a strong magnetic field. Finally, using our equation of state, we compute the structure of spin polarized strange quark star at different temperatures and magnetic fields. [ABSTRACT FROM AUTHOR]

Abstract: The first-principles calculations based on the density functional theory have been employed to explore the electronic structure and magnetic properties of the CoMnZ (Z = S, Se, Te) half-Heusler compound. CoMnTe is predicted to be half-metallic ferromagnet with an energy gap of 1.04 eV in the minority spin and a completely spin polarization at the Fermi level. CoMnS and CoMnSe compounds are nearly half-metallic with spin polarization of 98.9 and 97.9%, respectively. All compounds have a total magnetic moment of 4 μB/f.u., which agrees with the Slater–Pauling rule. CoMnTe compound keeps half-metallicity within a wide range of lattice constants between 5.65 and 6.05 Å. Under tetragonal distortions, high spin polarization at the Fermi level is maintained for the CoMnTe compound. [Copyright &y& Elsevier]

Abstract: By means of spin polarized density functional theory with the GGA+U framework, the reaction mechanism of CH3OH oxidation on the Co3O4 (110)-B and (111)-B surfaces has been investigated. Adsorption situation and a part of reaction cycle for CH3OH oxidation are clarified. Our results indicated that: i) U value can affect the calculated energetic result significantly; ii) CH3OH can adsorb with surface lattice oxygen atom (O2f/O3f) to form Co O bond directly, and the adsorption of CH3OH and its decomposition products on (110)-B is more stable than on (111)-B, which means CH3OH prefers Co3+ better than Co2+; iii) on the (110)-B surface, CH3OH can form CO2, H2O and adsorbed H atom. But on the (111)-B surface, CH3OH can just form formaldehyde (CH2O) and adsorbed H atom, this means oxidative capacity of (110)-B (Co3+) is higher than (111)-B (Co2+). The possible reasons corresponding to the high oxidative of (110)-B come from both Co3+ and O2f: Co3+ tends to bind adsorbed species for further decomposition and O2f tends to bind more hydrogenation atom involved in methanol due to its low-coordinates number compared to that of O3f. [Copyright &y& Elsevier]

• Above room temperature half metallic ferromagnetism. • Quantum spin of electrons leading the charge with multifunctional properties. • Exchange mechanism certifies the ferromagnetism by electron spin rather than clustering. • Half metallic ferromagnetism and 100% spin polarization. The recent development of electronic devices and control over their electro-magnetic and thermoelectric characteristics via electron spin has attracted a significant attention. Herein, we have addressed magnetic and thermoelectric calculations of K 2 MZ 6 (M = Os, Ir, and Z = Cl, Br) by quantum simulations. By comparing energies in antiferromagnetic, and ferromagnetic states, it turns out that lower energy corresponds to ferromagnetic (FM) states. Further, to confirm structural stability of FM state, tolerance factor was utilized. The Curie temperature has been reported by Heisenberg classical model. Moreover, the band structures (BS) and density of states (DOS) were analyzed to categorize half metallic (HM) ferromagnetism. To deeply understand the governing Half metallic ferromagnetism, the partial DOSs was tackled by p-d hybridization, exchange energies, and double-exchange model. The system is 100% spin polarized which is assured by integer magnetic moment. [ABSTRACT FROM AUTHOR]