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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]

In the framework of density functional theory (DFT) using Tran--Blaha modified Becke--Johnson exchange potential approximation (TB-mBJ), the structural, electronic, optical and mechanical, characteristics of cubic fluoroperovskites TiXF3 (X = Zn, Cu) are investigated. The structural properties, including equilibrium lattice constant, the bulk modulus (B) and its pressure derivative (B') are studied. Both the compounds are found to be stable structurally in its cubic form. The elastic characteristics, i-e anisotropy factor (A), Poisson's ratio (v), elastic constants, Young's modulus (E), and shear modulus (G) are investigated. The values of v and B/G ratio indicates that TiZnF3 and TiCuF3 compounds are ductile and brittle in nature respectively and exhibit anisotropy. In addition, these materials are resistant to plastic deformation due to the high G value. The electronic band structure, density of states (DOS) verifies the semiconducting and metallic nature with energy band gap of 5.4 and 0 eV of TiXF3 (X = Zn, Cu) compounds respectively. Ionic bonding character is found in both TiXF3 (X = Zn, Cu) compounds. Calculations of the optical spectrum like energy loss function L(ω), optical conductivity σ(ω), absorption coefficient α(ω), reflectivity R(ω), refractive index n(ω), and extinction coefficient k(ω) are carried out for the energy range 0 eV-13.5 eV. It is reported that n( ω), k( ω), and α( ω) exhibit identical characteristics as ε1( ω) and ε2( ω) and σ(ω) respectively. The thermoelectric properties study shows the very high value of ZT for TiCuF3. Since the above properties for these compounds are computed for the first time, therefore, no theoretical or experimental data is available for the comparison. [ABSTRACT FROM AUTHOR]

This work displays the structural, electronic, elastic, optical, and magnetic properties in spin-polarized configurations for cubic fluoroperovskite A B F 3 (A = Tl, B = Nb, V) compounds studied by density functional theory (DFT) by means of the Tran-Blaha-modified Becke-Johnson (TB-mBJ) approach. The ground state characteristics of these compounds, i.e., the lattice parameters a 0 , bulk modulus (B), and its pressure derivative B ′ are investigated. The structural properties depict that the selected compounds retain a cubic crystalline structure and have stable ground state energy. Electronic-band structures and DOS (density of states) in spin-polarized cases are studied which reports the semiconducting nature of both materials. The TDOS (total density of states) and PDOS (partial density of states) studies in both spin configurations show that the maximum contributions of states to the different bands is due to the B-site (p-states) atoms as well as F (p-states) atoms. Elastic properties including anisotropy factor (A), elastic constants, i.e., C11, C12, and C44, Poisson's ratio (υ), shear modulus and (G), Young's modulus (E) are computed. In terms of elastic properties, the higher (bulk modulus) "B" and ratio of "B/G" yield that these materials exhibit a ductile character. Magnetic properties indicate that both the compounds are ferromagnetic. In addition, investigations of the optical spectra including the real ( ε 1 ω ) and imaginary ( ε 2 ω ) component of the dielectric function, refractive index n ω , optical reflectivity R ω , optical conductivity σ ω , absorption coefficient α ω , energy loss function L ω , and electron extinction coefficient k ω are carried out which shows the transparent nature of T l V F 3 and T l N b F 3 . Based on the reported research work on these selected materials, their applications can be predicted in many modern electronic gadgets. [ABSTRACT FROM AUTHOR]

We utilized the WIEN2K code within the DFT framework to comprehensively investigate Ba 2 WBˈO 6 (Bˈ = Mn, Fe, Co, Ni, Zn) double perovskite compounds. Structural stability, assessed by Goldsmith's tolerance factor (t G), revealed values close to unity, indicative of stable cubic perovskite structures. The Birch-Murnaghan's equation of state optimization determined ground states, unveiling trends in lattice constant (a0) and bulk modulus (B) for different cations. Structural and phonon stability were confirmed by negative energy formation and real frequencies in phonon calculations. DFPT results affirmed the thermodynamic stability of all compounds. Electronic band structure calculations identified Ba 2 WMnO 6 and Ba 2 WNiO 6 as conductors, while Ba 2 WCoO 6 and Ba 2 WZnO 6 were insulators with 3.7 eV and 3.8 eV band gaps, respectively. Ba 2 WFeO 6 demonstrated semiconducting properties with a 2.37 eV band gap. Density of States (DOS) analysis supported the electronic band structure. Optical conductivity analysis revealed increasing values at higher energy ranges, followed by gradual decreases, differing between conductors and insulators. Absorption coefficient indicated potential suitability for optoelectronic devices, and refractive index analysis highlighted trends in material transparency. To understand fundamental properties, thermodynamic characteristics (thermal expansion coefficient, heat capacities, Debye temperature) were analyzed across a wide pressure (0–30 GPa) and temperature (0–1600 K) range. [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]

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]

The increasing research of advanced materials with tremendous compositional and structural degrees of variation, identifying and discovering new materials for a specific application is a challenging task. Here, we report for the first time the predicted structural, optoelectronic, and mechanical properties of germanium based AGeF3 (A = Ga and In) halides Perovskites using the density functional theory computational approach. The tolerance factor "τ" is computed for both the materials and is found to be 0.91 for InGeF3 and 0.89 for GaGeF3 which indicates the structural stability of these perovskites crystal structures. The optimized crystal structural parameters for both the compounds are found to be 4.476 Å for InGeF3 and 4.422 Å for GaGeF3 by performing the fit using Birch–Murnaghan for the unit cell energy verses unit cell volume. Using the optimized lattice constants all the basic physical properties are computed. From the results of electronic properties it is determined that both the compounds depict a semiconductor nature with having an indirect (R-M) band gap of 1.48 eV for InGeF3 and 0.98 eV for GaGeF3. To explore the potential of these selected compounds the optical properties within the energy range of 0 eV up to 40 eV incident photon are computed for the prospective optoelectronic applications. Moreover, the mechanical properties for both the materials are computed using the IRelast package and the values of cubic elastic parameters estimates that AGeF3 (A = Ga and In) halides Perovskites are mechanically stable, hard to scratch, ductile and anisotropic. We are fully confident on the precision and accuracy of our reported results and reveals that the applications of germanium based AGeF3 (A = Ga and In) halides Perovskites compounds can be deemed in photovoltaic and in modern semiconducting industries. [ABSTRACT FROM AUTHOR]

This study conducts a comprehensive exploration of the structural, electronic, elastic, and optical properties of HfXO 3 (X=Be, Mg) perovskite compounds, employing density functional theory (DFT) within the WIEN2k code. Employing the Birch Murnaghan fitting technique, our structural evaluation establishes the structural stability of these materials, with optimized lattice constants underscoring their stability at specific values. By harnessing the capabilities of the IRelast software, we have determined elastic constants and characterized the anisotropic tendencies, disclosing that both compounds exhibit a pronounced degree of anisotropy. Moreover, an in-depth investigation into electronic attributes, facilitated by the modified Becke–Johnson potential, uncovers these materials as indirect narrow band gap semiconductors, with calculated band gaps of 1.14 eV for HfBeO 3 and 0.8 eV for HfMgO 3 serving as vital indicators of their electronic character. Furthermore, we delve into the optical traits of these materials, revealing their photon transparency within the energy spectrum of 0 eV to 15 eV. These key optical properties encompass dielectric functions, refractive index, optical conductivity, absorption coefficient, extinction coefficient, energy loss function, and reflectivity. This comprehensive exploration offers a holistic understanding of the optical behaviors exhibited by these materials. By skillfully combining structural, electronic, elastic, and optical analyses, this study significantly contributes to the comprehension of HfXO 3 (X=Be, Mg) perovskites, forging a path for their potential applications and serving as a foundation for future research endeavors. [ABSTRACT FROM AUTHOR]