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Based on density functional theory (DFT), the electronic, structural, and optical properties of bismuth oxyfluoride (BiOF) are investigated by using various exchange–correlation functionals. The local density approximation (LDA), Perdew-Burke-Ernzerhof generalized gradient approximation (PBE-GGA), Perdew-Burke-Ernzerhof generalized gradient approximation for solids (PBEsol), and Wu-Cohen (WC) functionals are implemented in Wien2k software. Modified Becke-Johnson (mBJ) and unmodified Becke-Johnson (umBJ) potentials are also applied to obtain an enhanced band gap. Spin–orbit coupling effect (SOC) is also taken into consideration due to the heavy Bi atom. When employing the PBE+umBJ potential, BiOF exhibits the most enhanced band gap energy, with a direct band gap energy of 3.72 eV. Moreover, optical properties such as dielectric functions, absorption coefficients, and optical conductivities are also calculated for photon energies up to ̴̴ 14 eV. In comparison to other available theoretical and experimental findings, the calculated results are in good agreement. [ABSTRACT FROM AUTHOR]

Hydrogen storage has gained popularity recently due to its advantages as an energy source. Research on hydrogen storage applications primarily focuses on evaluating the ability of newly introduced compounds to store hydrogen. We have analyzed the physical characteristics of Cesium-based double perovskites Cs 2 XGaH 6 (X = Al, Na) using the first-principles calculations incorporated in the Wien2K code. Exchange correlation is treated through two approximations, such as PBE-GGA, to compute the structural and mechanical traits of Cs 2 XGaH 6 (X = Al, Na), and mBJ approximation to compute the optoelectronic and transport characteristics. The mechanical stability and brittleness of Cs 2 XGaH 6 (X = Al, Na) compounds are revealed by the examination of the elastic stiffness constants. The thermodynamic and mechanical stabilities for double perovskites are assessed in detail. Electronic properties revealed indirect bandgap of 1.89 eV and 3.08 eV for Cs 2 AlGaH 6 and Cs 2 NaGaH 6 , respectively. The optical traits are evaluated using the Kramer-Kroing complex equation. Several optical characteristics for Cs 2 XGaH 6 (X = Al, Na) have been have been examined and calculated. In the ultraviolet UV spectrum, absorption spectra reveal a rise in the redshift. For hydrogen storage, Cs 2 XGaH 6 (X = Al, Na) are attractive contenders due to their low energy losses at maximum absorption and highest static refractive index values. The gravimetric hydrogen storage capacity has been achieved up to 1.62 wt% for Cs 2 AlGaH 6 and 1.64 wt% for Cs 2 NaGaH 6. Moreover, the Cs 2 AlGaH 6 is found to be effective for hydrogen reduction, while Cs 2 NaGaH 6 is has better performance for oxygen reduction. In conclusion, this study provides evidence that Cs 2 XGaH 6 (X = Al, Na) can be used as a viable solution for efficient hydrogen storage and photocatalytic activities. • First-principles calculations have been performed to investigate the photocatalytic and hydrogen storage capacity of Cs 2 XGaH 6 (X = Al, Na). • The optimization cures, negative formation energy and tolerance factor show the stability of the studied compounds. • For hydrogen storage, Cs 2 XGaH 6 (X = Al, Na) are attractive contenders due to their low energy losses at maximum absorption. • Photocatalytic properties show the excellent response of Cs 2 XGaH 6 (X = Al, Na) for solar hydrogen synthesis. [ABSTRACT FROM AUTHOR]

Cesium-based halide double perovskites have wide range of applications, and have emerged as a promising class of materials in the field of photovoltaic, optoelectronics and catalysis. In this manuscript, the Wien2K simulation code is used to analyze the effect of multiple potentials on the optoelectronic, mechanical and structural traits of Cs2InBiF6 by employing the FP-LAPW method. The electron–ion interactions are taken in account by using LDA, GGA-PBE-sol, WC-GGA, GGA-PBE and TB-mBJ approximations. The crystal structure is relaxed and the results are fitted by using Birch–Murnaghan equation. The elastic properties reveal that Born's stability criteria are fulfilled by C11, C12 and C44. Furthermore, the hardness factor and machinability index reveals that material is highly malleable. The band structure profiles reveals direct bandgap of 2.22 eV, 2.25 eV, 2.28 eV, 2.32 eV and 3.00 eV for LDA, PBE-sol, WC-GGA, GGA and mBJ potentials, respectively. The electromagnetic interaction with the material reports maximum polarization and dispersion in the UV region making this material viable for sunscreens, UV-blocking coatings, and photodetectors. [ABSTRACT FROM AUTHOR]

Materials with versatile physical properties are essential for contemporary physical society, especially in electronics, renewable energy, transportation, medicine, and more. This intact capability holds the potential for a revolutionary shift towards environmentally friendly renewable energy sources. Consequently, the exploration of materials that encompass multiple functions becomes highly imperative. This study is concentrated on comprehending the physical characteristics of elastic and optoelectronic materials to propose novel, highly efficient materials suitable for photovoltaic device applications. Within this paper, the fundamental study of fluoroperovskite properties in the context of density functional theory is undertaken, employing the full potential linearized augmented plane wave approach. Specifically, fluoroperovskite ZnXF3 (X = Sr, Ba) is scrutinized concerning its structural, electronic, optical, and elastic attributes. The optimized crystal structural parameters for both compounds are determined as 4.41 Å for ZnSrF3 and 4.52 Å for ZnBaF3, employing the Birch-Murnaghan fitting approach for the unit cell energy versus unit cell volume. All fundamental physical properties are subsequently calculated using these optimized lattice constants. To address strongly correlated electron systems, the recently developed Modified Beck-Johnson potential is employed in this research. The tolerance factor "τ" is computed for both materials, yielding values of 0.98 for ZnSrF3 and 0.86 for ZnBaF3, affirming the structural stability of these perovskite crystal structures. The analysis of electronic properties reveals that both compounds exhibit a metallic behavior, for ZnXF3 (X = Sr, Ba) fluoroperovskites. Furthermore, the research explores the potential of these selected compounds by computing their optical properties within the energy range of 0–14 eV for incident photons, with a focus on potential optoelectronic applications. Additionally, mechanical properties for both materials are assessed using the IRelast package, with results indicating that ZnXF3 (X = Sr, Ba) fluoroPerovskites are mechanically stable, resistant to abrasion, ductile, and anisotropic. The precision and accuracy of the reported findings provide strong support for the potential applications of zinc-based ZnXF3 (X = Sr, Ba) fluoroperovskites in photovoltaic and modern semiconductor industries. [ABSTRACT FROM AUTHOR]

A new group of halides AgXF3 (X = Cr, Zr) compounds having perovskite structures were studied via the first principle approach supported on DFT, coded within WEIN2K and their properties were extensively investigated. Both AgCrF3 and AgZrF3 materials were confirmed to have the stability in the cubic structures because of having the Gold-Schmidt tolerance factor values in the range of stability. The band-gap information of all these materials were gathered by using the method of the modified Becke-Johnson potential. The metallic nature was found for the studied materials. The material AgCrF3 showed the greater tendency to restrain both the alteration in shape as well as in volume. Both AgXF3 and AgXF3 materials the showed nature of ductility, which was confirmed from both the Poisson's ratio and Pugh's ratio calculations and also the ionic nature of bonding was detected for all the studied materials. Moreover, the high optical reflectivity for both compounds are found. The obtained metallic nature and high optical reflectivity make them appropriate for electrode material and reflective coating. [ABSTRACT FROM AUTHOR]

In this study, we present the findings of a comprehensive investigation using first-principles methods to analyze the physical characteristics of the structural, electronic, optical, and elastic properties of the LmGaAs2 (Lm = In, Eu, Ta) chalcopyrites. The calculated equilibrium parameters exhibit a high level of agreement with the experimental counterparts that are currently available, thereby providing evidence of the accuracy of the outcomes that were reported. The elastic properties, such as bulk modulus, shear modulus, Young's modulus, and Poisson's ratio, have been derived related to mechanical stability and anisotropic sound velocities. Based on the examination of the energy band dispersions, it has been determined that the investigated compounds exhibit semiconductor properties. These compounds possess direct band gaps within the 1.4–2.0 eV range, specifically positioned within the visible spectrum. The determination of the origins of the electronic states that make up the energy bands is achieved through the utilization of the Partial Density of States diagrams. Frequency-dependent linear optical parameters are calculated within an energy range of 0 to 14 eV for investigated chalcopyrites for both spin channels of compounds. The large value of birefringence in a wide frequency range ensures phase-matching capabilities. The materials exhibit potential sources for solar cells and LED applications in the optoelectronic industry. [ABSTRACT FROM AUTHOR]

This article examines the optoelectronic and transport properties of ZnxAxSiGeN4 (A = Mn, Eu) through a comprehensive study. The study utilizes first-principles density functional theory (DFT) calculations with the Wien2k code. The optimized structural parameters, including the tolerance factor, critical radius, and formation energy, were initially determined. The energy band structure, densities of electronic states, and energy dependence of the optical functions were determined. The observed phenomenon exhibits a reduction in the energy difference between the valence and conduction bands for the materials under investigation. Precisely, the band gaps were measured to 4.1 eV, 2.0 eV (up)/2.8 eV (dn), and 0.8 eV (up)/2.4 eV (dn), respectively, for the respective doping of Eu and Mn. It has been determined that the material exhibits a direct band gap with a transition occurring along the Γ–Γ symmetry point. The electronic interband changes responsible for the observed optical spectra were identified. The thermoelectric parameters, such as the Seebeck coefficient, electrical and thermal conductivities, and figure of merit, were calculated using the standard Boltzmann transport theory in parallel. Based on our findings, it has been determined that the compounds under investigation exhibit promising characteristics that make them viable contenders for utilization in thermoelectric applications. The process of doped compounds Zn0.95Eu0.05SiGeN4 and of Zn0.95Mn0.05SiGeN4 has the potential to alter the characteristics of the material significantly, suggesting being promising for utilization in emerging fields such as advanced electronics and photovoltaic. [ABSTRACT FROM AUTHOR]

We evaluate the structural, optoelectronic, and mechanical characteristics of the novel Rb2CaSnCl6 and Rb2CaSnI6 through density functional theory within the WIEN2K framework. The formation energies and volume optimization provide evidence for the structural stability of these compounds. The optimized lattice constants for Rb2CaSnCl6 and Rb2CaSnI6 are found to be 11.21 Å and 12.45 Å, respectively while their respective formation energies are calculated as − 2.5 Ry and − 1.6 Ry. Similarly, the grounds state energies are calculated − 31,184.32 Ry and − 111,074.60 Ry. We find that Rb2CaSnCl6 is an insulator with a bandgap energy of 3.50 eV when the modified Becke-Johnson (mBJ) approximation is applied and that Rb2CaSnI6 is directly semiconducting with a wide bandgap energy of 2.70 eV. Evaluations of mechanical stability show that both materials are mechanically stable and their constituent atoms are bound together by ionic interactions, indicated by the positive value of Cauchy's pressure: 46. 32 and 21.93 for Rb2CaSnCl6 and Rb2CaSnI6, respectivley. Nevertheless, our investigation showed that Rb2CaSnI6 behaves as a ductile material while Rb2CaSnCl6 is brittle. We also investigate a variety of optical characteristics such as dielectric function, refraction, reflectivity, energy loss function, and extinction coefficient. The static dielectric function was found to be 2.9 and 4.3 for Rb2CaSnCl6 and Rb2CaSnI6, respectively. Rb2CaSnI6 exhibited greater optical conductivity, indicative of it being a better metallic than the Rb2CaSnCl6. The optical investigation suggests that these materials have a great deal of promise for cutting-edge optoelectronic applications, especially in the ultraviolet (UV) spectrum due to their large electronic band gap. These results offer a solid basis for future research into these intriguing materials by experimentalists. [ABSTRACT FROM AUTHOR]

Due to their stability, eco-friendly nature, lack of lead, and high performance, double perovskites are promising materials for solar cells, thermoelectric generators, and renewable energy applications. This study investigates the structural, dynamical, elastic, and optoelectronic properties of Cs2TlGaX6 (X = Cl, F) compounds using first-principles calculations with the WIEN2k code. While the PBE-GGA method accurately predicts ground state properties, it underestimates band gaps. To address this, the TB-mBJ approach, known for precise semiconductor bandgap calculations, was used. Calculated formation energy confirmed the thermodynamic stability of both compounds, with Cs2TlGaF6 (-2.81 eV) more stable than Cs2TlGaCl6 (-1.79 eV). Imaginary frequencies absence indicates phonon stability. Structural optimization plots reveal stable unit cell configurations, and elastic property analysis confirms their ductile nature and resistance to cracking. Cs2TlGaCl6 behaves as an indirect wide band gap semiconductor (3.78 eV), suitable for various applications, while Cs2TlGaF6 exhibits insulating behavior with a larger band gap (6.23 eV). Optical properties were also calculated, suggesting potential applications in optoelectronics, photonics, and semiconductors within the ultraviolet energy ranges. [ABSTRACT FROM AUTHOR]

The present study employs rigorous DFT analysis using WIEN2k for the best suitability of the Cr2O3 as an electron transport layer, synergetic with nontoxic and thermally stable CsSnCl3 perovskite solar energy storage device, configured as FTO/Cr2O3/CsSnCl3/CBTS/Au. The main objective of our investigation is to improve the device performance by optimizing thickness, carrier concentration, bulk defect density of each layer, interface defects, operating temperature, as well as the impact of parasitic elements on device performance. SCAPS‐1D tool was used to optimize the novel device architecture. The simulation results reveal that a CsSnCl3 layer with an optimized thickness of 800 nm and a doping concentration of 1 × 1015 cm−3 yields noteworthy outcomes, specifically, champion efficiency (휂) of 22.01% along with an open‐circuit voltage (Voc) of 1.12 V, a short‐circuit current (Jsc) of 23.86 mA/cm2, and a fill factor of 81.65%. These improved findings were compared with existing theoretical and experimental reported data and found to exhibit the best performance. The present research substantially enhances the understanding of eco‐friendly CsSnCl3 perovskite solar cell optimization, thereby extending its applicability to future photovoltaic and optoelectronic devices. [ABSTRACT FROM AUTHOR]

The physical performance of the double half-Heusler compounds, namely ScNbRh2Bi2 and ScTaRh2Bi2 based on structural, electronic, optical and thermoelectric properties, has been investigated. The information gathered showed that both substances are stable nonmagnetic alloys. The electronic characteristics of ScNbRh2Bi2 and ScTaRh2Bi2 exhibit direct energy band gaps of 0.629 and 0.903 eV, respectively. The optical properties reveal a high absorption coefficient that increases steadily over the visible light spectrum. These substances also have high visible-spectrum reflectivity, making them perfect for optoelectronic uses like solar and photovoltaic cells. Furthermore, these materials are an extraordinary possibility for thermoelectric applications because of their high figure of legitimacy and Seebeck coefficient (S) values. However, there are no hypothetical or exploratory data for these compounds to compare with what we reported. We think that the ongoing review will be beneficial for upcoming experimenters trying to tentatively assemble these synthetic compounds. [ABSTRACT FROM AUTHOR]

Ab initio Density Functional Theory calculations, using the full-potential linearized augmented plane wave (FP-LAPW) method with the generalized gradient approximation and Hubbard-U term were used to investigate the structural properties, whereas Tm-mBj used for electronic, optical thermodynamic properties of Al-based fluoroperovskite compounds AlMF3 (M = Ca and Cd). With a careful investigation of the contribution from various bands, using total and partial density of state curves, electronic band structure analysis, identified AlCaF3 and AlCdF3 as direct band gap materials. Calculations of optical spectra spanning from 0 to 40 eV were done, including real and imaginary parts of the dielectric function, optical reflectivity, absorption coefficient, optical conductivity, refractive index, and extinction coefficients. In the present work, thermodynamic properties are also investigated by using Gibbs package integrated in quasi harmonic. Because of their unique optical properties, the materials are suggested to have potential applications in optoelectronic devices. [ABSTRACT FROM AUTHOR]

This study involves the investigation of the double perovskite A2NbTbO6 (A = Ca, Sr, and Ba) using the PBE-GGA approximation under the quantum-based DFT (density functional theory) within the WIEN2k code. The materials A2NbTbO6 (A = Ca, Sr, and Ba) are cubic crystals with space group Fm3m-225 and non-magnetic behavior. The structural, electrical, optical, and thermoelectric characteristics of the given materials have been investigated. Band gap and density of state calculations are used to explain the electronic properties of the materials under study with the PBE-GGA approximation. The results made it abundantly evident that the materials are pure semiconductors with direct band gaps. Complex dielectric function, refractive index ƞ(ω), extinction coefficient K(ω), optical conductivity σ(ω), absorption coefficient α(ω), reflectivity R(ω), and loss parameter L(ω) are analyzed to explain the optical behavior of the materials. Charge carrier concentration (n), electrical conductivity (σ/t), Seebeck coefficient (S), power factor (PF), thermal conductivity (K/t), specific heat capacity (Cv), and magnetic susceptibility (χ) are investigated to find the material's thermal properties which show the ability of materials in green energy (eco-friendly) production devices and good candidates for optoelectronics especially for solar cell. The BoltzTraP code, which is part of the WIEN2k code, is used to calculate these properties. The cubic compounds Ca2NbTbO6, Sr2NbTbO6, and Ba2NbTbO6 have band gaps of 1.93 eV, 1.89 eV, and 1.87 eV, respectively and are direct band gap materials are confirmed from the band gap structures. By these calculations, all the characteristics are examined to produce new materials for sustainable devices and renewable energy applications like solar cells, and optoelectronics. [ABSTRACT FROM AUTHOR]

BMS (BaMgSiO4) is a promising candidate for inorganic photochromatic materials with excellent opto-electronic properties. Because of its applications in high density optical memory and LEDs, the host matrix BMS has piqued the interest of academics all over the world. In this study, the generalized gradient (GGA and GGA + U) approximations were used to examine the electronic structure and optical properties of BaMgSiO4:Eu, including dielectric function, refractive and extinction coefficients, the optical conductivity, reflectivity, and absorption spectra. It is found that the substitution of Eu ions has reduced the energy band gap of BaMgSiO4. Our findings show that the band gap and optical characteristics of BaMgSiO4 compound are better described by GGA + U method. Future research can use this study as a guide, and it contributes to extending the capabilities of BaMgSiO4 materials to optical applications. The results of this study suggest that phosphide semiconductors could be used in solar cells. [ABSTRACT FROM AUTHOR]

This study provides a comprehensive analysis of the cubic double‐perovskite compound Pb2ScTaO6, exploring its structural stability, electronic, optical, and mechanical properties. The material's response to hydrostatic pressure, using density functional theory with the FP‐LAPW approach, is investigated. The analysis, validated by experimental and theoretical data, reveals Pb2ScTaO6's semiconductor nature with a bandgap of 3.129 eV, which decreases under hydrostatic pressure. Furthermore, the assessment of the material's elastic constants confirms its mechanical stability and the optical properties across ultraviolet and infrared spectra suggest potential applications in optoelectronic devices. [ABSTRACT FROM AUTHOR]

This study employs a first-principles approach to comprehensively examine the structural, electronic, optical, and magnetic properties of the thermodynamically stable scintillating double perovskite halides A 2 N a T a X 6 ( A = C s , R b ; X = C l , B r , I ). The dynamic stability of these materials were explained based on deduced phonon properties. Our analysis reveals that these compounds exhibit intriguing electronic behavior with spin polarization, demonstrating half-metallicity. In spin-up, the band gap is found to be zero, while in spin-down, it falls within the range of 3 to 4 eV with the incorporation of DFT+U corrections. Notably, the optical properties assessment highlights the exceptional UV and high-energy absorption capabilities of A 2 N a T a I 6 , making it a promising candidate for scintillation applications in particle detection. This research sheds light on the unique and versatile properties of these materials, with implications for various technological and scientific applications. [ABSTRACT FROM AUTHOR]

The pursuit of new materials with tailored properties is essential for advancing technology. This research focuses on GaXF3 (X = Se, Si) fluoroperovskites, utilizing the density functional theory approach. The study begins by assessing structural properties, revealing stable configurations for both compounds. The results from phonon calculations confirm the thermodynamic stability of the compounds. The relationship between elastic constants, confirms their mechanical stability. Elasticity analysis using the IRelast package indicates their resilience, anisotropic characteristics, and mechanical stability. Electronic properties, including band structure, density of states, and electronic band gaps, show that both materials have a metallic nature. Additionally, optical properties, such as dielectric constants, absorption coefficients, and refractive indices, are explored, providing insights into their interactions with light for optoelectronic applications. Optical property calculations for both GaSeF3 and GaSiF3, indicate their potential suitability for use in optoelectronic devices, particularly LEDs, due to their absorption within the UV–Vis range. These results encompass properties such as reflectivity, refractive index, and absorption coefficients, indicating their relevance to potential applications in optoelectronic devices. These findings enhance our understanding of these materials and lay the groundwork for future advancements in advanced materials science. [ABSTRACT FROM AUTHOR]

In this research, the structural properties, phonons, mechanical stability, and optoelectronic properties of silicon-based Ca2TiSiO6 ordered double perovskites oxides are computed employing the DFT approach within the WIEN2K quantum mechanical code. The LDA, PBE-GGA, and TB-mBJ potentials are used, and it is found that the TB-mBJ potential gives more accurate results for optoelectronic properties. Our computed results for structural properties are entirely consistent with the experimental results. The calculations of phonons and the criterion of Born-Huang's mechanical stability confirm the dynamical, structural, and mechanical stability of quaternary Si-based Ca2TiSiO6 material. The elastic constants Cij, Pugh ratio B/G, and Poisson's ratio ʋ verify that the interested material is stiff, malleable, and resistant to shear strain. The computed spectral curves for various optical parameters reveal the robust responsiveness of the Ca2TiSiO6 material to UV wavelengths. This suggests promising applications in ultraviolet detectors, photo-catalysis, photo-detectors, solar cells, and other optoelectronic devices where efficient light absorption is essential for optimal functionality. Our research on silicon-based Ca2TiSiO6 double perovskite oxide will provide a base framework for experimental materials scientists. [ABSTRACT FROM AUTHOR]

To explore a good candidate for solar cell applications as an alternative to lead-independent materials, we calculated the structural and mechanical stability of the Rb2TlSbX6 (X = Cl, Br, I) compounds with PBEsol potential. The optoelectronic and thermoelectric behaviors of these compounds are computed with TB-mBJ potential. Our results indicate that these materials possessed excellent structural, mechanical, and thermal stability on the basic values of their Goldsmith’s, elastic parameters and negative formation energies. The dynamic stability is observed through phonon dispersion curve and found that all materials are dynamically stable. The computed values of Poisson and Pugh ratios and a positive value of Cauchy’s pressure indicate the ductile nature of these materials. We observed the low direct bandgaps for Rb2TlSbCl6, (1.486 eV), Rb2TlSbBr6 (2.07 eV), and Rb2TlSbI6 (1.04 eV) unlike the majority of halide double perovskite family have large bandgap values in literature. In addition, the computed optical and thermoelectric characteristics of the Rb2TlSbX6 (X = Cl, Br, I) materials show large values of absorption and optical conductivity with low reflectivity and energy loss at small energy ranges. According to these findings, all these halogen-based double perovskite materials have the potential to be employed as photovoltaic absorb materials in solar cell applications. Furthermore, the large values of the Seebeck coefficient, high-power factor and figure of merit (ZT) at room temperature also ensured their significance for thermoelectric generators.

Double perovskites have garnered significant attention for use in renewable energy applications, particularly solar cells. The development of organic-inorganic hybrid halide perovskite solar cells has advanced rapidly over the last ten years. In this article, fundamental aspects of transport properties of Cs2AgGaCl6 have been illustrated using DFT-based simulation. Constantly is covered that the calculated lattice constant agreed with the available experimental data. With an indirect band gap, the electronic profile demonstrates a semiconducting nature. Reporting bandgap of 1.20 eV for Cs2AgGaCl6. This bandgap remains suitable for solar cell semiconductors. The computed values of effective masses reveal that effective masses of holes are greater than those of electrons. Further various optical parameters have also been examined. The absorption of light in the visible and ultraviolet spectrums is guaranteed by the absorption bands 2.7–4.2 eV and 3.5–4.5 eV. We believe that such insights offer a new starting point and a framework for future research. So, knowledge and drive gained from these studies will stimulate more theoretical investigation into novel perovskite-based materials with novel applications.

Effective hydrogen storage is a crucial requirement for harnessing hydrogen as an energy source. Among various storage methods, solid-state hydrogen storage holds promise but necessitates extensive investigation. This study employs density functional theory within the WIEN2k code to improve the desorption temperature and kinetic properties of MgH 2 by introducing Be in combination with transition elements (Ni, Cu, and Zn). The gravimetric hydrogen storage capacity for all studied compounds exceeds 6%. Introduction of different transition elements with Be leads to improvements in formation and cohesive energies, as well as in desorption temperature. Mechanical stability, determined through elastic constants, is confirmed for all hydrides meeting the Born stability criteria. Detailed analyses encompass bonding characteristics, shear modulus, bulk modulus, Cauchy pressures, elastic anisotropy, and Vickers Hardness tests. Electronic properties reveal that Mg 2 BeZnH 8 exhibits the semiconductor nature, and properties are further improved by using TB-mBJ approach. Electronic charge density calculations unveil interatomic bonding nature. Numerous previously unexplored thermodynamic aspects of these hydrides have been investigated and are now presented. • Orthorhombic Mg 2 BeTMH 8 (TM = Ni, Cu and Zn) have been investigated by using density functional theory. • The gravimetric hydrogen storage capacity for all compounds studied exceeds 6%. • Mg 2 BeZnH 8 has low desorption temperature than other two studied hydrides. • All the studied materials are mechanically stable and hard. • Electronic properties reveal that these hydrides exhibit semiconductor nature, except Mg 2 BeNiH 8. [ABSTRACT FROM AUTHOR]

Context and results: The study examines the physical characteristics of Co2ZrZ compounds using the Wien2k code and the Anisimov and Gunnarsson approach. Results show metallic attributes in Co2ZrBi and Co2ZrAs, while Co2ZrPb exhibits semi-metallic tendencies. Energy gap evaluations reveal significant infrared transitions, indicating altered electron mobility compensated by increased ultraviolet absorption. These compounds have potential in space solar energy applications due to UV light absorption capabilities, especially in Co2ZrPb. The study also identifies optical phenomena like “super-luminescence” and plasmatic oscillations. Computational and theoretical techniques: The study uses computational techniques like Wien2k calculation code and Hubbard parameter calculations to investigate Co2ZrPb, a compound with potential for space energy applications. Energy gap assessments are conducted using GGA and mBJ-GGA methods. The study also analyzes the optical behavior of the compounds, including infrared and ultraviolet absorption. The BoltzTraP code is used for thermoelectric investigations, revealing a P-type charge carrier predominance in Co2ZrPb. This comprehensive approach provides valuable insights into electrical conductivity and thermoelectric properties. [ABSTRACT FROM AUTHOR]

Double perovskites have harvested considerable attention in the realm of solar cells and renewable energy applications. Therefore, in this current study, we explored the structural, electronic, and optical properties of Rb2InGaCl6 and Rb2InGaF6 using DFT-based simulations with WIEN2K codes. It is unequivocally established that both compounds demonstrate structural and mechanical stability. Structural stability is further evaluated using Goldsmith's tolerance factor (τG). The τG values of 4.29 and 3.77 are considered acceptable for ensuring the stability of cubic structures for Rb2InGaCl6 and Rb2InGaF6 respectively. It is determined that both compounds are stable elastically and possess ductile characteristics, allowing them to undergo plastic deformation without fracturing. Our investigation reveals indirect band gaps of 1.7 eV (semiconductor) for Rb2InGaCl6 and 4.8 eV (insulator) for Rb2InGaF6. These diverse band structures open up exciting possibilities for optoelectronic applications. Regarding optical properties, the spectral curves of various parameters are examined in the range of 0 eV to 15 eV incident photon energy. The findings reveal the exceptional optical performance of Rb2InGaCl6 and Rb2InGaF6, particularly by their notably high absorption coefficients α(ω). Specifically, Rb2InGaCl6 demonstrates a remarkable absorption of 6.635 at 2.05 eV, while Rb2InGaF6 exhibits a significant absorption of 3.91 at 4.78 eV. The optical conductivity σ(ω) attains peak values, reaching 4.60 for Rb2InGaCl6 and 2.85 for Rb2InGaF6. Furthermore, the optical reflectivity R(ω) peaks at 13.60 eV for Rb2InGaCl6 and 6.30 eV for Rb2InGaF6. Lastly, the energy loss functions L(ω) attain their highest values of 0.57 and 7.58 for Rb2InGaCl6 and Rb2InGaF6, respectively. These results collectively emphasize the impressive optical characteristics of these compounds across a range of energy levels. These findings suggest promising potential energy applications for these materials, particularly in influencing electromagnetic radiation within the ultraviolet (UV) spectrum ranges. [ABSTRACT FROM AUTHOR]

First-principles calculations using Density Functional Theory (DFT) and the Wien2k package are used to analyze the structural, electrical, optical, and elastic characteristics of Li-based chloride perovskites LiXCl3 (X = Ca, Ba). The structural analysis demonstrates that these compounds are stable and have the space group pm-3m (no. 221). The calculations show that these materials possess an indirect band gap. For elastic properties, the Pugh's ratio (compound ductility), elastic constants, anisotropy factor, Poisson's ratio, and bulk modulus are analyzed. In 0–30 eV energy range, optical parameters such as dielectric function, extinction coefficient, reflectivity, absorption coefficient, refractive index, and optical conductivity, are measured. Optical properties, i.e. dielectric function, extinction coefficient, refractive index, absorption coefficient, reflectivity and optical conductivity, are evaluated in 0–30 eV energy range. The calculations show that these materials possess large band gap and are structurally anisotropic, making these better candidates for scintillator applications. [ABSTRACT FROM AUTHOR]

The basic structural, optical, elastic, and electronic properties are investigated in this research for QZnCl3 (Q = Li and Na) ternary centrosymmetric chloroperovskites compounds utilizing the DFT approach. The integrated TB-mBJ exchange–correlation potential within the WIEN2K computational simulation package serves for precise outcomes. The structural optimization is done by fitting the Birch-Murnaghan equation of state (EOS) for the primitive unit cell energy versus primitive unit cell volume. The parameters from the optimized fitted curves, Goldsmith's tolerance factor (tG), and octahedral coefficient predict the stable cubic structure of QZnCl3 (Q = Li and Na) centrosymmetric ternary chloroperovskites compounds. The elastic parameters which include cubic elastic constants (ECs), elastic moduli (E), Poisson's ratio (v), anisotropy factor (A), and the Pugh ratio (B/G) investigated through IRelast code display the mechanical stability, ductility, and toughness of interested centrosymmetric compounds. Predicted electronic band structures and densities of states (DOS) display that LiZnCl3 and NaZnCl3 possess an indirect (R-Γ) band gap of 3.82 eV and of 3.91 eV respectively, confirming that both the materials are wide band gap semiconductors. In optical properties, the spectral curves of several parameters are observed from 0 eV up to 15 eV incident photons energy, and it is revealed that the centrosymmetric chloroperovskites QZnCl3 (Q = Li and Na) are optically effective at high absorption coefficients (α(ω)), optical conductivity (σ(ω)), optical reflectivity (R(ω)), and energy loss (L(ω)) functions. The potential energy applications can be deemed for these materials, influencing electromagnetic radiation in the ultraviolet (UV) spectrum ranges. In a nutshell, the research on QZnCl3 (Q = Li and Na) demonstrate that these centrosymmetric materials are noteworthy and can be applied as energy storage systems, scintillators, and many other components of present electronic devices. [ABSTRACT FROM AUTHOR]

This study examined the potential consequences of doping on Sr2YGaX2O7(X = Fe, Rh) photovoltaic properties. Density functional theory (DFT) was used to calculate pyrochlore oxides' energy band structure and optical characteristics using the full potential linearized augmented plane wave (FP-LAPW) method. The generalized gradient approximation (GGA + U) was utilized to treat the exchange and correlation potential. We studied the metallic atoms Fe, Rh, Y, and Ga orbital electronic states. The utilization of the complex dielectric function facilitated the computation of various optical properties such as the energy band dispersion statistics, absorption coefficient, reflectivity, energy loss function, refractive index, extinction coefficient, and real optical conductivity parameters. We employed Boltzmann transport theory to delve deeper into the electrical transport characteristics (specifically thermoelectric properties) of Fe and Rh-doped pyrochlore oxides in the temperature range of 0–800 K. It is observed that the Sr2YGaRh2O7 compound indicated higher values of ZT 0.9, 1.25 for 50 K and 800 K, respectively. Further, both the compounds exhibit p-type nature as their seebeck coefficient shows a positive region between 50 and 800 K. The materials with strong thermoelectric properties are assumed in high reflectivity zone and potentially effective in solar heating. [ABSTRACT FROM AUTHOR]

Metal halide perovskites have gained prominence in optoelectronics recently, thanks to their unique optical and electrical properties, along with their adaptable morphologies. The current work reports the electronic, structural, mechanical, optical, and thermoelectric traits of Rb2TlInBr6 for the very first time. The confirmation of thermodynamic stability is evidenced by the negative value of the formation energy, while structural stability is established by calculating values for the tolerance factor and octahedral tilting. Elastic constants (Cij) and mechanical attributes are evaluated to assess perovskites' ability to resist external strains. Electronic band structures computed with GGA and mBJ potentials depict a semiconducting nature containing indirect bandgap of 1.8 and 2.42 eV, respectively. Optical characteristics of Rb2TlInBr6 ensure that it can be used effectively for optoelectronic applications. An insight into the thermoelectric characteristic is assessed through BoltzTraP code. The electrical conductivity and ZT reveal the ability of Rb2TlInBr6 to be utilized in green energy devices. [ABSTRACT FROM AUTHOR]

To improve the performance of materials, we employ first-principles techniques based on density functional theory (DFT) implemented in the Wien 2k code to study perovskites Ba3CaAx2O9. We used the Birch-Murnaghan fit, tolerance factor, and formation energy to determine the structural stability of these materials. Structurally stable compounds Ba3CaAx2O9 have a tolerance factor of 0.7, 1.1, and 0.9, respectively, and a formation energy of −3.04 eV, −1.98, and −1.12 eV. We used the proposed mBJ+U potential to assess the properties of the present materials, providing insight into their nature. Band gaps of 1.5–3.2 eV for Ba3CaAx2O9 (Ax = Nb, Mo, Rh) indicate that they are indirect semiconductors. We also calculate the density of states (DOS) for both materials, and our results for the energies of the band gaps agree with those from the band structure. Absorption and optical conduction are observed to occur in the UV region, and all investigated materials are transparent to low-energy photons. Our investigation into the optical characteristics of these materials suggests they could be promising candidates for application in optoelectronic devices. Finally, the Seebeck coefficient, electrical conductivity, thermal conductivity, power factor, and figure of merit have been calculated to investigate the thermoelectric efficiency of the triple perovskites based on semi-classical Boltzmann theory. The findings suggest that triple perovskites may be a promising candidate for optoelectronic and thermoelectric applications. [ABSTRACT FROM AUTHOR]

Fluoroperovskites, a subgroup of perovskite materials, have gained substantial scientific interest due to their outstanding optoelectronic properties and potential applications in electronic devices, such as solar cells, LEDs, and transistors. These unique properties originate from the crystal structure, enabling adaptable bandgap engineering. This paper investigates the structural, elastic, electronic, and optical properties of LiXF3 (X = Cd, Hg) using Density Functional Theory in WIEN2K. The stable cubic nature of LiCdF3 and LiHgF3 with lattice constants of 4.396 Å and 4.560 Å, respectively, is revealed. Elastic property analysis confirms mechanical equilibrium and ductility, while band structure calculations indicate indirect band gaps of 2.64 eV and 3.38 eV for LiCdF3 and LiHgF3, respectively, from (M − Γ). Optical properties within a 15 eV range are correlated with the electronic structure, providing a comprehensive understanding of Li-based fluoroperovskites' physical attributes. [ABSTRACT FROM AUTHOR]

Structural, electronic, magnetic and elastic characteristics of do half-Heusler alloys CsXB (X = Mg and Sr) are investigated by using First-principles study based on density functional theory. Full-potential linearized augmented plane wave method is used to study these compounds in WIEN2k. The generalized gradient approximation that Perdew–Burke–Ernzerhof developed is used to deal with the exchange correlation function. The elastic characteristics have been employed with the IRelast package, which is already included into WIEN2K. Band structure and density of states are used to describe electronic properties which indicate the half-metallic nature of these compounds. Both CsMgB and CsSrB have minimum energies for spin channel. According to our calculations, CsMgB has a gap of 0.44 eV for spin down channel while CsSrB shows a gap of 0.34 eV for spin up channel. These two compounds exhibit half-metallic characteristic with total integer magnetic moment per formula unit, i.e., 2.00002 for CsMgB and 2.00004 µB of CsSrB which is in well accordance with the Slater–Pauling rule [Mtot = (8−Ztot) µB]. Both compounds are mechanically stable and reveal ductile nature. The obtained results reveal that CsSrB and CsMgB compounds are HM ferromagnets with perfect spin polarization in the absence of transition metals which make them promising candidates for spintronic devices. [ABSTRACT FROM AUTHOR]

Double perovskites (DPs) have attracted considerable attention for their potential in optoelectronic and thermoelectric applications. In this study, we utilize the WIEN2K code, which relies on density functional theory, to analyze the structural, electronic, mechanical, and optical properties of X2NaTlF6 (X = Cs, Rb). To assess the material's structural durability, we determine the tolerance factor, and thermodynamic stability is examined through formation energy and phonon calculations. Mechanical stability is confirmed through the relationship between elastic constants, specifically C11 - C12 > 0, C11 > 0, C11 + 2C12 > 0, and B > 0. Furthermore, an analysis of elasticity using the IRelast package reveals their resilience, anisotropic properties, and mechanical stability. The calculated elastic moduli indicate that Rb2NaTlF6 displays ductile behavior, while Cs2NaTlF6 demonstrates brittleness, depending on the specific elastic constant under consideration. Utilizing the modified Beck and Johnson potential (TB-mBJ), we determine band gaps of 1.23 eV for Rb2NaTlF6 and 1.64 eV for Cs2NaTlF6 DPs. Additionally, we investigate optical properties, including refractive index, dielectric constant, and reflectivity, providing further insights into their behavior. Optical property calculations for both compounds suggest their potential suitability for use in optoelectronic devices, particularly LEDs, owing to their UV-Vis range absorption characteristics. [ABSTRACT FROM AUTHOR]

In this study, first-principles numerical computations for zinc-blende ternary alloys (In1−xAlxSb) are performed concerning elastic, structural, electronic, thermal, and optical properties. This study is carried out using the "full-potential linearized augmented-plane-wave plus local-orbital, (FP-L(APW + lo))" approach framed within "density functional theory" and realized in the WIEN2k computational package. From our computational work, performed at the level of generalized gradient approximation suggested by Wu and Cohen (GGA-WC) for the exchange–correlation functional, we see that our obtained results for the structural parameters of the title alloys (In1−xAlxSb) are increasing with increasing concentration x, and by and large, follow the Vegard's law. To predict reliable electronic and optical properties "Tran–Blaha modified Becke–Johnson (mBJ)" potential approach was employed. We note, except at x = 1 and x = 0.75, electronic band gaps are of direct nature for evaluated concentrations of the title alloys. In addition, noticeable variation is noted in the optical parameters with x concentration. For analyzing the thermal character of the title alloys, the "quasi-harmonic Debye model" scheme is used. Comparison of obtained results with experimental and predicted ones is found in good agreement where available. Hence our computational study of the title alloys endorses the reliability of our investigations and might offer a valuable platform for future predictions and experimental work as well as suggest that title material is the best candidate for optoelectronics. The optical quantities obtained using mBJ show low energy loss and reflectivity and high absorption capability in the infrared and visible regions for In1−xAlxSb, making these materials potential candidates in solar cell applications. [ABSTRACT FROM AUTHOR]