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The latest discovery of ferromagnetism in atomically thin films of semiconductors Cr2Ge2Te6 and CrI3 has unleashed numerous opportunities for fundamental physics of magnetism in two-dimensional (2D) limit and also for technological applications based on 2D magnetic materials. To exploit these 2D magnetic materials, however, the mechanisms that control their physical properties should be thoroughly understood. In this paper, we present a comprehensive theoretical study of the magnetic, electronic, optical and magneto-optical (MO) properties of multilayers (monolayer (ML), bilayer (BL) and trilayer) as well as bulk CrI3, based on the density functional theory with the generalized gradient approximation plus on-site Coulomb repulsion scheme. Interestingly, all the structures except the BL, are found to be single-spin ferromagnetic semiconductors. They all have a large out-of-plane magnetic anisotropy energy (MAE) of ∼0.5 meV/Cr, in contrast to the significantly thickness-dependent MAE in multilayers of Cr2Ge2Te6. These large MAEs suppress transverse spin fluctuations and thus stabilize long-range magnetic orders at finite temperatures down to the ML limit. They also exhibit strong MO effects with their Kerr and Faraday rotation angles being comparable to that of best-known bulk MO materials. The shape and position of the main features in the optical and MO spectra are found to be nearly thickness-independent although the magnitude of Kerr rotation angles increases monotonically with the film thickness. Magnetic transition temperatures estimated based on calculated exchange coupling parameters, calculated optical conductivity spectra, MO Kerr and Faraday rotation angles agree quite well with available experimental data. The calculated MAE as well as optical and MO properties are analyzed in terms of the calculated orbital-decomposed densities of states, band state symmetries and dipole selection rules. Our findings of large out-of-plane MAEs and strong MO effects in these single-spin ferromagnetic semiconducting CrI3 ultrathin films suggest that they will find valuable applications in semiconductor MO and spintronic nanodevices.

The effect of halide composition on the structural, electronic, and optical properties of CsPb(Br1−xClx)3 perovskite was investigated in this study. When the chloride (Cl) content of x was increased, the unit cell volume decreased with a linear function. Theoretical X-ray diffraction analyses showed that the peak (at 2θ = 30.4°) shifts to a larger angle (at 2θ = 31.9°) when the average fraction of the incorporated Cl increased. The energy bandgap (Eg) was observed to increase with the increase in Cl concentration. For x = 0.00, 0.25, 0.33, 0.50, 0.66, 0.75, and 1.00, the Eg values calculated using the Perdew–Burke–Ernzerhof potential were between 1.53 and 1.93 eV, while those calculated using the modified Becke−Johnson generalized gradient approximation (mBJ–GGA) potential were between 2.23 and 2.90 eV. The Eg calculated using the mBJ–GGA method best matched the experimental values reported. The effective masses decreased with a concentration increase of Cl to 0.33 and then increased with a further increase in the concentration of Cl. Calculated photoabsorption coefficients show a blue shift of absorption at higher Cl content. The calculations indicate that CsPb(Br1−xClx)3 perovskite could be used in optical and optoelectronic devices by partly replacing bromide with chloride.

We gauge the importance of self-interaction errors in density functional approximations (DFAs) for the case of water clusters. To this end, we used the Fermi–Löwdin orbital self-interaction correction method (FLOSIC) to calculate the binding energy of clusters of up to eight water molecules. Three representative DFAs of the local, generalized gradient, and metageneralized gradient families [i.e., local density approximation (LDA), Perdew– Burke–Ernzerhof (PBE), and strongly constrained and appropriately normed (SCAN)] were used. We find that the overbinding of the water clusters in these approximations is not a densitydriven error. We show that, while removing self-interaction error does not alter the energetic ordering of the different water isomers with respect to the uncorrected DFAs, the resulting binding energies are corrected toward accurate reference values from higher-level calculations. In particular, self-interaction–corrected SCAN not only retains the correct energetic ordering for water hexamers but also reduces the mean error in the hexamer binding energies to less than 14 meV/H₂O from about 42 meV/H₂O for SCAN. By decomposing the total binding energy into manybody components, we find that large errors in the two-body interaction in SCAN are significantly reduced by self-interaction corrections. Higher-order many-body errors are small in both SCAN and self-interaction–corrected SCAN. These results indicate that orbital-by-orbital removal of self-interaction combined with a proper DFA can lead to improved descriptions of water complexes.

It is a challenge to characterize the acid properties of microporous materials in either experiments or theory. This study presents the crystal structure, acid site, acid strength, proton siting, and IR spectra of HSAPO-34 from the SCAN + rVV10 method. The results indicate: the crystal structures of various acid sites of HSAPO-34 deviate from the space group of R3¯; the acid strength inferred from the DPE value likely decreases with the proton binding sites at O(2), O(4), O(1),and O(3), contrary to the stability order in view of the internal energy; the calculated ensemble-averaged DPE is about 1525 kJ/mol at 673.15 K; and the proton siting and the proton distribution are distinctly influenced by the temperature: at low temperatures, the proton is predominantly located at O(3), while it prefers O(2) at high temperatures, and the proton at O(4) assumedly has the least distribution at 273.15–773.15 K. In line with the neutron diffraction experiment, a correction factor of 0.979 is needed to correct for the calculated hydroxyl stretching vibration (ν(O-H)) of HSAPO-34. It seems that the SCAN meta-GGA method, compensating for some drawbacks of the GGA method, could provide satisfying results regarding the acid properties of HSAPO-34.

A “best-of-both-worlds” van der Waals (vdW) density functional is constructed, seamlessly supplementing the strongly constrained and appropriately normed (SCAN) meta-generalized gradient approximation for short- and intermediate-range interactions with the long-range vdW interaction from rVV10 , the revised Vydrov–van Voorhis nonlocal correlation functional. The resultant SCAN+rVV10 is the only vdW density functional to date that yields excellent interlayer binding energies and spacings, as well as intralayer lattice constants in 28 layered materials. Its versatility for various kinds of bonding is further demonstrated by its good performance for 22 interactions between molecules; the cohesive energies and lattice constants of 50 solids; the adsorption energy and distance of a benzene molecule on coinage-metal surfaces; the binding energy curves for graphene on Cu(111), Ni(111), and Co(0001) surfaces; and the rare-gas solids. We argue that a good semilocal approximation should (as SCAN does) capture the intermediate-range vdW through its exchange term. We have found an effective range of the vdW interaction between 8 and 16 Å for systems considered here, suggesting that this interaction is negligibly small at the larger distances where it reaches its asymptotic power-law decay.

In this paper, we use the functional density theory method with GGA and GGA + U approximations to study the structural, electronic, magnetic, thermal and thermoelectric properties of the complex quadruple perovskite CdCu 3 Fe 4 O 12 . The magnetic state between Cu and Fe is anti-ferromagnetic, and for Cu–Cu and Fe–Fe is ferromagnetic to have the most stable phase namely the ferrimagnetic phase. According to the energy study and the total moment to be evaluated is of the order of – 12 μB, where the ferrimagnetic phase of the quadruple perovskite CdCu 3 Fe 4 O 12 is the most stable. This structure is characterized by semi-metallic behavior with a gap equal to 0.22 eV and medium polarization of spins according to the GGA approximation. The calculation of the total density of states reveals the existence of a mixed valence for Cu and Fe. The thermal and thermoelectrical properties at room temperature for the perovskite complex CdCu 3 Fe 4 O 12 compound are: The Seebeck coefficient S = - 5 , 09 μ V K −1 , electrical conductivity 3.63 × 10 20 Ω - 1 cm - 1 s - 1 , heat capacity 390 J mol −1 K −1 , and the power factor 10 10 W m −1 K −2 s −1 .

Mycoplasma gallisepticum (MG) can cause chronic respiratory disease (CRD) in chickens. While several studies have reported the inflammatory functions of microRNAs during MG infection, the mechanism by which exosomal miRNAs regulate MG‐induced inflammation remains to be elucidated. The expression of exosome‐microRNA derived from MG‐infected chicken type II pneumocytes (CP‐II) was screened, and the target genes and function of differentially expressed miRNAs (DEGs) were predicted. To verify the role of exosomal gga‐miR‐451, Western blot, ELISA and RT‐qPCR were used in this study. The results showed that a total of 722 miRNAs were identified from the two exosomal small RNA (sRNA) libraries, and 30 miRNAs (9 up‐regulated and 21 down‐regulated) were significantly differentially expressed. The target miRNAs were significantly enriched in the treatment group, such as cell cycle, Toll‐like receptor signalling pathway and MAPK signalling pathway. The results have also confirmed that gga‐miR‐451‐absent exosomes derived from MG‐infected CP‐II cells increased inflammatory cytokine production in chicken fibroblast cells (DF‐1), and wild‐type CP‐II cell–derived exosomes displayed protective effects. Collectively, our work suggests that exosomes from MG‐infected CP‐II cells alter the dynamics of the DF‐1 cells, and may contribute to pathology of the MG infection via exosomal gga‐miR‐451 targeting YWHAZ involving in inflammation.

Background: Salmonella is a prevalent contaminant in food sources, capable of infecting multiple host species and contributing to notable public health threats and economic burdens. Early and accurate detection of contamination is essential to ensure food safety. Advancements in molecular biology have underscored the importance of epigenetic elements, especially microRNAs (miRNAs), in modulating the interactions between pathogens and their hosts. Objectives: This research investigates the diagnostic potential of gga-miR-126-5p and gga-miR-148a-3p by analyzing their expression profiles in infected chicken meat samples. Methods: In this cross-sectional study, a total of 75 chicken meat samples, comprising 50 Salmonella-positive and 25 Salmonella-negative controls selected from a larger screening pool, were assessed. Following RNA extraction and complementary DNA (cDNA) synthesis, real-time polymerase chain reaction (RT-PCR) was employed to determine the expression levels of the selected miRNAs. Results: Analysis revealed a marked elevation in the expression of both gga-miR-126-5p and gga-miR-148a-3p in samples contaminated with Salmonella compared to the control group. Conclusions: The observed upregulation of these two miRNAs in infected tissues highlights their potential as biomarkers for Salmonella detection, as well as their possible involvement in host immune modulation. Future research is warranted to further elucidate their functional targets and clinical significance in infection monitoring.

Structural, electronic, elastic and thermodynamic properties of Ni2LaZ (Z = As, Sb and Bi) Heusler alloys based on rare earth element have been investigated using full-potential linear muffin-tin orbital (FP-LMTO) method within generalized gradient approximation (GGA) in the frame of density functional theory (DFT). By using total energy variations, the independent elastic constants and their pressure dependence have been determined. Also, anisotropic parameter (A), shear modulus (G), Young modulus (E), Poisson’s ratio (ν), ratio (B/G) are calculated. Using quasi-harmonic Debye model, thermodynamic properties of Ni2LaZ (Z = As, Sb and Bi) Heusler alloys are investigated in temperature range 0–1200 K and pressure range 0–50 GPa. The temperature and pressure effects on the unit cell volume, bulk modulus (B), heat capacities (Cv) at stable volume, (Cp), Debye temperatures (θD), Gibbs energies (G), thermal expansion coefficients (α) and entropies (S) are determined from non-equilibrium Gibbs functions. This study allows to understand deeply the structural and thermodynamic properties of Ni2LaZ (Z = As, Sb and Bi) Heusler alloys in shortest time and cost-effective.

The structural, electronic, optical, and thermo-electric properties of LuNiBi and LuNiSb Half-Heusler have been studied using a full potential linearized augmented plane-wave (FP-LAPW) method. The results of the calculations presented in this work were obtained through the use of different approximations GGA-PBE, GGA-PBEsol, GGA-WC, and mBJ-GGA. The electronic band structures exhibit that the LuNiBi and LuNiSb alloys have a small indirect gaps in the valence band and the conduction band at points Г and X, revealing the semiconductor character in both compounds. The complex dielectric function ε (ω), optical conductivity σ (ω), extinction coefficient к (ω), refractive index n (ω), and reflectivity R (ω) as a function of photon energy are calculated using mBJ-GGA approximation, that is yielding results in good accordance with available experimental data. On the other hand, the variations of the thermal conductivity, power factor, figure of merit ZT, Seebeck coefficient, and electrical conductivity, as a function of temperature, have been investigated. Most of the optical and thermoelectric properties of LuNiSb and LuNiBi materials are not available in the literature; this makes the present work as a detailed comparative study between both compounds and opens the path for other future accurate theoretical studies to find the promising substitute for the interesting and more efficient thermoelectric device in industry.