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This research provides a comprehensive investigation of the double perovskite compound Ba2CrWO6, emphasizing its structural, electronic, magnetic, thermal, optical, and elastic properties. Analysis revealed that Ba2CrWO6 exhibits a direct half-metallic gap of 1.05 eV along the (X–X) direction, accompanied by a net magnetic moment of 2.00 μB, significantly influenced by the presence of chromium. In terms of optical characteristics, Ba2CrWO6 demonstrated high absorption rates, indicating its potential applications in optical devices, particularly in ultraviolet (UV) light detection, photodetectors, and UV lasers. Furthermore, the elasticity study indicated that this compound possesses weak brittleness, facilitating handling during manufacturing processes. Density Functional Theory (DFT) calculations, using the full-potential linearized augmented plane wave (FP-LAPW) method, employed the generalized gradient approximation (GGA), modified Trans-Blaha (TB-mBJ) approach. Additionally, the GGA + U method, which includes the Hubbard correction term (U), was utilized to address strong electron correlation effects within the compound. The spin–orbit coupling (SOC) was included to see its effects on the total and partial densities of states, but the results are almost similar to calculations without spin orbit coupling. [ABSTRACT FROM AUTHOR]

This study investigates the structural, electronic, and thermoelectric properties of three Double Half-Heusler (DHH) compounds: Hf2FeNiSb2, Nb2Co2GaSb, and ScNbCo2Sb2, using the full-potential linearized augmented plane wave (FP-LAPW) approach based on density functional theory (DFT) and implemented in the Wien2k software. In this analysis, we have used the GGA-PBE approximation for treating the exchange-correlation potential and the TB-mBJ-GGA approximation to enhance the energy band gaps, aiming to align them more closely with the experimental values. According to our research results, we can say that these compounds exhibit stability in the non-magnetic phase and exhibit no total magnetic moment. The determined band gap values for these compounds indicate their semiconducting nature, with indirect gap values of 0.42, 0.55, and 0.67 eV for Hf2FeNiSb2, Nb2Co2GaSb, and ScNbCo2Sb2, respectively. These values are determined using the TB-mBJ-GGA approximation, which is recommended for improving energy gap values and approaching experimental values. Moreover, these compounds demonstrate remarkable figure of merit (ZT) values approaching unity, indicating their potential as promising materials for thermoelectric applications. Specifically, the thermoelectric properties of Hf2FeNiSb2 and ScNbCo2Sb2 improve at low temperatures (0–100K), while Nb2Co2GaSb displays the best thermoelectric efficiency in the temperature range of 500–800K. [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]

Context and results: In this study, we have explored the electronic and optical properties of A2AlAgCl6 (A = Rb, Cs), revealing their potential applications in UV devices. Our investigation demonstrates that Rb2AlAgCl6 and Cs2AlAgCl6 possess remarkable mechanical and thermodynamic stability, alongside direct band gaps of 4.25 eV and 4.20 eV, respectively. The optical properties, including the dielectric function, absorption coefficient, and reflectivity, underscore the suitability of these materials for UV device applications. This work serves as a foundational reference for future experimental endeavors aiming to leverage these characteristics for practical uses in scientific research. Computational and theoretical techniques: The study utilizes first-principles calculations based on the Wien2k code, employing GGA-PBE and mBJ exchange–correlation functional to analyze the cubic structure of the space group Fm-3m. Detailed computational analyses were conducted to investigate the band structure, density of states, and optical properties, particularly focusing on Cs2AlAgCl6. This methodological approach not only confirms the materials' impressive stability and optical characteristics but also provides a robust framework for assessing their potential in UV technology applications. Our computational strategy offers insights into the effectiveness of these methodologies for future experimental validation and practical deployment in the research domain. [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]

We have carried out a theoretical calculation based on density functional theory using full-potential linearized augmented plane-wave method implemented within the wien2k program to investigate the structural, electronic, elastic, thermodynamic and thermoelectric properties of full Heusler alloys Ba2AgZ (Z = Bi, Sb). The exchange and correlation potential are treated by different approximations: LDA, GGA-PBE and mBJ-GGA. The electronic band structures of both alloys show them as narrow indirect band gap semiconductor. Moreover, these compounds are characterized by a high value of the figure of merit (ZT) (close to the unity) and Seebeck coefficient (S) which makes them promising candidates for thermoelectric applications. Thermal properties, including the heat capacity Cv, the entropy S and the Debye temperature ( θ D ), have been successfully computed using the quasi-harmonic Debye model. The mechanical properties reveal that the studied compounds are mechanically stable and can be synthesized experimentally. It is noteworthy that the present calculation is a first quantitative theoretical prediction of the electronic, elastic, thermodynamic and thermoelectric properties of these compounds. We believe that the present study will be useful for experimentalists for experimental synthesis of these compounds in future. [ABSTRACT FROM AUTHOR]

In this paper, we have studied and carried out a theoretical calculation using the full-potential linearized augmented plane-wave method (FP-LAPW), based on density functional theory (DFT) and implemented in the wien2k program to investigate the structural, electronic, and magnetic properties of Ba2ErReO6 material, within the generalized gradient approximation (GGA) and generalized gradient approximation with effective Hubbard U parameter (GGA + U). According to the electronic properties and according to the GGA approximation, the results show that our material Ba2ErReO6 has a metallic character with integral magnetic moment of 5.1 µB; however, through employing the GGA + U method, the material Ba2ErReO6 radically changes in nature due to the fact that it presents a half-metallic character with a direct band gap at Γ-Γ direction in spin down channel and this for values of U ≥ 2 eV; in addition, we see that the greater the Hubbard coefficient U, the greater the energy gap of the material in its semi-conducting nature (in the spin down channel) until reaching the value of 1.96 eV corresponding to a value of 8 eV for the Hubbard coefficient U. This is a predictive study of the double perovskite compound Ba2ErReO6 based on rare earths Er and therefore constitutes a serious reason for further theoretical investigations as well as adequate experiments and this for very useful and widespread applications such as spintronic, high-performance electronic devices, and optic applications. [ABSTRACT FROM AUTHOR]

In this work, we have studied the structural, optoelectronic, elastic and thermoelectric properties for halides doubles perovskites compounds K2GeSiX6 (X = F , Cl, Br and I). Based on the linearized augmented plane wave method with full potential (FP-LAPW) method, the previous properties are treated within GGA-PBE and the modified Beck–Johnson correction (mBJ-GGA) approximations. The results show that these compounds are stable in the nonmagnetic phase (NM). Due to the electronic properties, our results indicate that all these compounds have a semiconductor behavior with a direct bandgap at Γ - Γ direction with values of 2.30 eV, 0.632 eV, 0.259 eV and 0.124 eV for K2GeSiF6, K2GeSiCl6, K2GeSiBr6 and K2GeSiI6, respectively. In addition, the high dielectric constant, high absorption coefficient and high optical conductivity suggest that the materials have the potential for a wide absorption range that starts from the visible to the ultraviolet of optoelectronic applications, including solar or photovoltaic cells. Finally, the thermoelectric properties, through the calculation of the various related parameters (Seebeck coefficient, electrical conductivity, thermal conductivity, power factor and figure of merit), show that the materials K2GeSiBr6 and K2GeSiI6 can be promising for predispositions thermoelectric and by comparing the thermoelectric parameters of the two materials mentioned above, at room temperature, the material K2GeSiI6 has better performance than the material K2GeSiBr6, due to a significantly higher Seebeck coefficient (234.32 μ V/°K), a fairly substantial power factor (1. 1 7 × 1 0 1 1 Wk − 2 m − 1 s − 1 ) and a fairly low thermal conductivity (0. 4 8 × 1 0 1 4 WK − 2 m − 1 s − 1 ). [ABSTRACT FROM AUTHOR]

Structural, electronic and optical properties for halide double perovskites compounds K2GeSnBr6 and K2GeSnI6 are studied in this work. Based on the (FP-LAPW) method, the previous properties are treated within the (GGA-PBE) and the (mBJ-GGA) approximations. The results show that these compounds are stable in the non-magnetic phase (NM). Electronic properties indicate that these compounds have a semiconductor behavior with a direct band gap. The calculated formation energy and cohesive energy indicate that these alloys have good chemical stability. High absorption coefficient and high reflectivity prove that these materials are appropriates for optoelectronic applications, including solar and photovoltaic cells. [ABSTRACT FROM AUTHOR]

In this paper, we have investigated the structural, optoelectronic and elastic properties of AGeI3 (A = K, Rb and Cs) using the density functional theory with generalized gradient approximation (GGA) for potential exchange correlation. The modified Becke–Johnson (mBJ-GGA) potential approximation is also used for calculating the optoelectronic properties of the material. The results show that the band structure of the perovskites AGeI3 (have a semiconductor behavior with direct band gap at R–R direction, the gap energy values calculated with mBJ-GGA, for each compound as following: 0.58, 0.63, and 0.71 eV, respectively. The optical properties, such as real and imaginary parts of the dielectric functions, refractive index, reflectivity, conductivity and absorption coefficient are investigated. As results, these compounds are competent candidates photovoltaic application like light harvester. [ABSTRACT FROM AUTHOR]