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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]

This research work investigates the structural, electronic, optical, and thermoelectric characteristics of VFeZ (Z = N and P) half‐Heusler compounds. The study employs the full‐potential linearized augmented plane wave (FP‐LAPW) method integrated into the WIEN2K algorithm, serving as the underpinning framework for density functional theory (DFT) analysis. In the study, we use the PBE generalized gradient approximation (PBE‐GGA) to identify numerous parameters associated with structural and elastic properties. Lattice parameter results are in agreement with previous outcomes. Moreover, computed elastic parameters satisfy the criterion for stability. In the cubic structure VFeZ (Z = N and P) is ductile, to enhance the computations of electronic characteristics, Tran and Blaha's modified Becke‐Johnson potential (TB‐mBJ) is used. Our simulations demonstrate that the materials exhibit semiconductor behavior, with a direct band gap for VFeZ (Z = N and P). Strong UV absorption is found via optical experiments suggest compounds are suitable for optical application. Furthermore, study of the thermoelectric properties suggests its application in the thermoelectric generators. [ABSTRACT FROM AUTHOR]

In this study, we investigate the halide perovskite material Cs 2 LiLuCl 6 using both density functional theory (DFT) and time-dependent density functional theory (TD-DFT) approaches. Our analysis focuses on the structural, electronic, and optical properties of the material, conducted with the Quantum Espresso code. In order to confirm the structural stability of the material, we performed various tests including analysis of elastic constants, formation energy, tolerance factor, and phonon dispersion. Employing the generalized gradient approximation (GGA) and GGA+U, we determine that the material behaves as an insulator with a direct band gap of 5.3042 eV and 5.4245 eV, respectively. Additionally, DFT+U calculations were performed to study the dielectric function, reflectivity, absorption coefficient, and refractive index, revealing a high transmittance rate exceeding 90%. Under ideal conditions, the upper light yield (LYsc) is estimated to be 75 411 ph/MeV and 73 739 ph/MeV for the DFT and DFT+U methods, respectively. These results, along with the presence of lithium in Cs 2 LiLuCl 6 , highlight its potential for use in scintillation-based thermal-neutron detection applications. • Cs2LiLuCl6 is stable in a cubic structure as shown by its formation energy and phonon data. • Cs2LiLuCl6 exhibits insulating behavior with a direct band gap. • The material has high UV emissivity, improving scintillation applications. • Cs2LiLuCl6 achieves 75,411 photons/MeV (DFT) and 73,739 photons/MeV (DFT+U). [ABSTRACT FROM AUTHOR]

The electronic, elastic, structural, thermoelectric and optical parameters of Pb-based cubic perovskites P b R E O 3 (R E = C e , N d , G d) were calculated using the WIEN2k Package. The mechanical optimization and structural stabilities were evaluated. The found results are in full agreement with the experimental ones. The obtained elastic results show that these perovskites behave as stable ductile materials, and their higher Y value gives them rigid structures. The P b C e O 3 presents n-type semiconductor while P b R E O 3 (R E = N d , G d) exhibit p-type semi-conductors with gap energies of 2. 60 eV , 1. 02 eV and 1. 55 eV , respectively. The optical properties show that P b R E O 3 (R E = C e , N d , G d) have significant absorption in the visible light region with low reflectivity. The thermoelectric properties present a desired electrical performance at room temperature for all materials. For these generation of materials, the effect of RE on Pb-based cubic perovskite oxides can be exploited in manufacturing of thermoelectric, mechanic and optoelectronic devices. • Physical properties of PbCeO3, PbNdO3 and PbGdO3 were studied. • Structural and elastic properties present a stable behavior of the studied compounds. • The electronic properties indicate the semiconductor behavior of all studied. • Optical properties presents an important absorption coefficient in the visible region. • Thermoelectric properties show the charge carriers responsible of the conduction. [ABSTRACT FROM AUTHOR]

Various physical properties (electronic, optical and thermoelectric) of cubic perovskite oxides Sr X O 3 (X = Sc, Ge, Si) are investigated by using the density functional theory (DFT) within Wien2K code. This code is based on different approximations such as generalized gradient approximation GGA, PBEsol, LDA, WC and the modified Becke–Johnson exchange potentials (mBJ, nmBJ and unmBJ). Structural properties and the optimization have been calculated using PBEsol functional which showed a significant results that are in good agreement with the experimental ones. The results for physical properties such as electronic, thermoelectric and optical are analyzed in detail by using the nmBJ approximation. The obtained results present an opening gap for SrSiO 3 , SrGeO 3 and a metallic behavior for SrScO 3. An average of transmittance which is about 94% to 97% was observed in the range of visible light. The increase of electrical conductivity with temperature confirms the effect of thermal agitation on the concentration of charges carriers using BolzTrap2 Package. Lastly a phonon dispersion was made and show that for X = Ge and Si, the structure is relatively stable while SrScO 3 is dynamically unstable. These results prove the ability that these materials can be exploited in many applications and manufacturing of optoelectronics for Sensors. [ABSTRACT FROM AUTHOR]