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The zinc-based perovskites ZnLiX3 (X = Cl or F) were investigated for their structural, electronic, and optical properties using the WIEN2k package within density functional theory (DFT). Structural properties were calculated using the generalized gradient approximation (GGA), while the modified Becke-Johnson (mBJ) potential was applied for a more accurate description of the optical and electronic properties. Both compounds are confirmed to be stable, crystallizing in the cubic Pm-3 m (No. 221) space group. ZnLiCl3 has an indirect band gap of 0.30 eV between the Γ and M symmetry points, indicating semiconducting behaviour, while ZnLiF3 exhibits an indirect band gap of 5.45 eV, typical of an insulating material. The electronic states contributing to the band structure were analyzed using the total density of states (TDOS) and partial density of states (PDOS). Optical properties, evaluated in the energy range of 0–14 eV, reveal strong optical conductivity and absorption at higher energies, while both materials show transparency to lower-energy photons. These findings suggest that ZnLiCl3 and ZnLiF3 are suitable candidates for high-frequency UV optoelectronic device applications.

Herein, the investigation is presented to analyze the structural, electronic, optical, and thermoelectric features of Cs2XAgCl6 (X= Sc, Y) by applying the first principles approach. The confirmation of the stable structure of both compounds is reinforced by the negative values of formation enthalpies. The electronic band gaps (Eg) of 3.78/4.86 eV are computed for Cs2XAgCl6 /Cs2YAgCl6 through Tran-Blaha modified Becke-Johnson (TBmBJ) potential, correspondingly. The tolerance factor(τ) is found as 0.9 for Cs2ScAgCl6 and 1.0 for Cs2XAgCl6 which confirmed the stable cubic nature of both compounds. Optical factors like dielectric-function ε(ω), absorption coefficient α(ω), and others related parameters are analyzed within 0 to 10 eV of energy span. Both compounds demonstrated high absorption in the ultraviolet region, rendering them as well-suited materials for photovoltaic applications. The calculated values of refractive index for Cs2ScAgCl6 and Cs2XAgCl6 indicated super-luminescent characteristics in the ultraviolet region. For thermoelectric (TE) features, electrical conductivity (σ/τ), figure of merit (ZT), power factor (PF), thermal conductivity (k/τ), and Seebeck coefficient (S) are calculated using the BoltzTraP code. According to the findings, both materials are advocated as promising candidates for thermoelectric and optoelectronic applications. [ABSTRACT FROM AUTHOR]

• Structural Stability: ZnLiCl 3 and ZnLiF 3 crystallize in the cubic Pm-3 m (No. 221) space group, confirmed to be stable via DFT calculations using the WIEN2k package. • Band Gap Analysis: ZnLiCl 3 has an indirect band gap of 0.30 eV (semiconducting), while ZnLiF 3 has an indirect band gap of 5.45 eV (insulating), based on electronic band structure calculations. • Electronic Structure: The total and partial density of states (TDOS and PDOS) were analyzed, identifying the electronic states contributing to the band structure for both compounds. • Optical Properties: Both materials exhibit strong optical conductivity and absorption in the higher energy range (0–14 eV) and transparency to lower-energy photons, making them highly suitable for UV applications. • Application Potential: The study suggests ZnLiCl 3 and ZnLiF 3 as promising candidates for high-frequency UV optoelectronic devices due to their optical and electronic characteristics. The zinc-based perovskites ZnLiX 3 (X = Cl or F) were investigated for their structural, electronic, and optical properties using the WIEN2k package within density functional theory (DFT). Structural properties were calculated using the generalized gradient approximation (GGA), while the modified Becke-Johnson (mBJ) potential was applied for a more accurate description of the optical and electronic properties. Both compounds are confirmed to be stable, crystallizing in the cubic Pm-3 m (No. 221) space group. ZnLiCl 3 has an indirect band gap of 0.30 eV between the Γ and M symmetry points, indicating semiconducting behaviour, while ZnLiF 3 exhibits an indirect band gap of 5.45 eV, typical of an insulating material. The electronic states contributing to the band structure were analyzed using the total density of states (TDOS) and partial density of states (PDOS). Optical properties, evaluated in the energy range of 0–14 eV, reveal strong optical conductivity and absorption at higher energies, while both materials show transparency to lower-energy photons. These findings suggest that ZnLiCl 3 and ZnLiF 3 are suitable candidates for high-frequency UV optoelectronic device applications. [ABSTRACT FROM AUTHOR]

Ab-initio studies are employed to explore physical aspects of indium-based double halide perovskites Cs2InAgX6 (X = Cl, Br, I) using full-potential linearized augmented plane-waves method along with local orbitals. The electronic behaviors are observed by computing the band structures and density of states, which are determined by employing GGA-PBEsol approximation. The Tran–Blaha-modified Becke–Johnson (TB-mBJ) potential is then further applied. The use of TB-mBJ potential has revealed that direct band gap is exhibited by Cs2InAgX6 (X = Cl, Br, I), which are found agreeing with the literature. Various optical parameters are calculated to evaluate all three double perovskites to unveil their potential applications in optical devices. In addition, BoltzTraP code is used to explore the thermoelectric properties within the temperature range 100–800 K. The studied double perovskites have been suggested as highly appropriate candidates for the fabrication of a variety of renewable energy devices. [ABSTRACT FROM AUTHOR]

We provide a thorough study of the structural, elastic, electronic and magnetic properties of the perovskite solid solution of Sr1−xBaxFeO3 within the framework of density functional theory (DFT), using the full-potential linearized augmented planewave plus local orbital FP-(L)APW+lo method. The found results provide predictions for the mixed perovskite solid solution Sr1−xBaxFeO3 (x = 0.25, 0.5, 0.75) for which no experimental or theoretical data are presently available. These compounds were supposed to have a cubic ferromagnetic structure for all xcompositions. The GGA-PBE functional was chosen for the prediction of the structural properties, in particular the lattice parameter, the bulk modulus and its pressure derivative as well as the cohesive energy. For testing the mechanical stability of the Sr1−xBaxFeO3 compounds, we have studied their elastic constants and it has been found that these compounds are mechanically stable in their cubic perovskite structure. Several parameters related to the elastic constants have also been predicted, in particular Young’s modulus, the shear modulus, Poisson’s ratio, the anisotropic factor and the Debye temperature (θD). For the correct treatment of the high correlation of 3d-iron electrons, the Hubbard correction and TB-mBJ potential were added to the GGA-PBE functional for the analysis of the electronic and magnetic properties of Sr1−xBaxFeO3. It has been found that they are half-metals with a total magnetic moment of ∼ 4µB [ABSTRACT FROM AUTHOR]

To compute the structural, electronic, optical, elastic, and thermoelectric (TE) characteristics of Cs 2 ScTlCl 6 and Cs 2 YTlCl 6 halide double perovskites, the first principles method is employed by using density functional theory (DFT) based full potential linearized augmented plane wave (FP-LAPW) scheme. Band structure (BS) and density of states (DOS) revealed the direct band gap (E g) of 4.44/5.22 eV for Cs 2 ScTlCl 6 /Cs 2 YTlCl 6 , correspondingly. To explore the thermodynamic and structural stability of the Cs 2 ScTlCl 6 and Cs 2 YTlCl 6 , the formation enthalpy (ΔH) and tolerance factor (τ) are computed. The optical absorption edges are located at 3.8 for Cs 2 ScTlCl 6 and 5.1 eV for Cs 2 YTlCl 6. The distinct absorption characteristics observed, particularly in the UV spectrum, suggest that both materials hold promise for use in advanced optoelectronic devices. Elastic constants for both compounds are predicted to determine mechanical features. The Poisson's ratio and Cauchy pressure (CP) depicted brittle nature of both perovskites. Furthermore, BoltzTraP program is utilized to examine TE features and the analysis of ZT spectrum reveals an increase in ZT, rising from 0.747 to 0.800 for Cs 2 ScTlCl 6 and from 0.740 to 0.802 for Cs 2 YTlCl 6 , as temperatures increase from 300 to 800 K. TE materials, with enhanced ZT values, hold promise for diverse applications, including efficient power generation, wearable technology, automotive systems, space exploration, and industrial processes. [ABSTRACT FROM AUTHOR]