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In the current work we studied the structural, elastics, electrical, optical, thermoelectric, as well as spectroscopic limited maximum efficiency (SLME) of oxide based Ba2AsBO6 (BNb, Ta) materials. All the calculations were performed using first-principles calculation by employing the WIEN2k code. We checked the stability in diverse forms such as optimization, phonon dispersion, mechanical, formation energy, cohesive energy, and thermal stability is computed. The semiconducting nature of these Ba2AsBO6 (BNb, Ta) systems is revealed by calculating the direct band gap values are 1.97 eV and 1.49 eV respectively. Additionally, we determined the optical properties which analyze the utmost absorption and transition of carriers versus photon energy (eV). Moreover, Ba2AsNbO6 has an estimated SLME of 32 %, making it an encouraging alternative for single-junction solar cells. Lastly, we studied the transport properties against temperature, the chemical potential for p-type and n-type charge carriers at various temperatures. At 300 K, the zT values are found to be 0.757 and 0.751 for Ba2AsBO6 (BNb, Ta) compounds respectively. Both materials were examined as having strong absorption patterns and an excellent figure of merit (ZT), indicating that materials are appropriate for daily life applications.

This article investigated the structure, optoelectronic characteristics, and transport properties of the Hg-based chalcopyrite HgAl2X4 (X = S, Se) using DFT. To calculate the optimized lattice constant, we applied Perdew-Burke-Ernzerhof’s generalized-gradient-approximation (PBEsol-GGA) and found calculated lattice constant of both chalcopyrites is reasonable compared to experimental values. In addition, modified Becke and Johnson (mBJ) potential were used to investigate the optoelectronic properties. Studied HgAl2S4 and HgAl2Se4 chalcopyrite compounds have a direct bandgap of 3.20 eV and an indirect bandgap of 2.60 eV, respectively. Projectile and total density of states were computed to check the maximum contribution of chalcopyrite HgAl2X4 (X = S, Se). HgAl2S4 and HgAl2Se4 chalcopyrite have a substantial optical absorption near 3.5 eV and 3.9 eV making them interesting for hetero-junction solar cell. Furthermore, based on measured results of large thermal properties, we discovered that the structures are thermally and mechanically robust in a cubic structure. Finally, the BoltzTrap code is used to study the figure of merit (ZT), power factor, Seebeck coefficient, and electrical and thermal conductivity of transport characteristics.

Based on the ab-initio calculations, we have investigated the electronic, optical, and thermal properties of pristine SnSe and doped with oxygen (O) and sulphur (S) at the Se-site at concentration of 3.125%. The calculated negative formation energy indicates the stability of the pristine SnSe and doped system. We find that pristine SnSe possesses a direct bandgap value of 0.90 eV having good comparable to experimental value. The doping of O and S tunes the bandgap of SnSe, which can be promising for photovoltaic devices. Further, for the technological applications of O-/S-doped SnSe, we have analyzed optical properties in terms of absorption of photon energy and polarization. Strong absorption peaks confirms the direct transition of electrons from valence band to conduction band. Moreover, the thermal properties are calculated in terms of electrical/thermal conductivities, Seebeck coefficient, and figure of merit (ZT). At room temperature the ZT values are calculated round about 0.41 for O- and S-doped SnSe, respectively. We expect that our calculated thermoelectric parameters of the O- and S-doped SnSe could pave a new route for the application in the thermoelectric devices.

A fascinating novelclass of double perovskites materials with interesting optoelectronic and transport features have been discovered. In the current study, optoelectronics and the transport properties of Rb2LiTlX6 (X = Cl, Br) were comprehensively examined. Structure stability was confirmed by calculating tolerance factor value and Born stability criteria. At the Γ-symmetry point, direct band gaps of 2.90 eV and 1.66 eV are observed, ensuring spectral response throughout ultra-violet to visible areas and used as potential candidates for solar cell applications. These are excellent compounds for optoelectronic applications because of their low scattering of light, refractive index range approximately from 1.5 to 2, and wide absorption band in visible areas. Furthermore, thermal properties with the name electrical conductivity, thermal conductivity, Seebeck coefficient, power factor, and figure of merits of double perovskites were studied. The figure of merits (ZT) values of both compounds are 0.43, and 0.51 at room temperature, which confirms that these materials are suitable for use in thermal devices.

The primary basis of renewable energy is transformation of light energy in the form of electrical energy that highly analyzed in past decade. By using Quantum espresso codethat based density functional theory, we have elucidated mechanical, electronic and optical properties of organic (CH3NH3)2AgMBr6 (M = Sb, Bi) halides. In order to treat exchange-correlation functional, we employed PBE generalized gradient approximations (GGA) to execute the mechanical and opto-electronic parameters. Our calculated results of Pugh's ratio and Poisson's ratio of both halides recommended the quality of ductility. In addition, calculations regarding electronic and optical properties are obtained by using GGA + U in-order-to deliberating the accurate band gap. The required indirect band gaps for opto-electronic applications are calculated as 0.1 eV/0.88 eV for (CH3NH3)2AgSb/BiCl6. Interestingly, significant absorption coefficients for both halides endorse that these are appropriate opto-electronic devices in near-visible and infra-red regions.

In this work, the structural, elastic, electronic, thermodynamic, optical, and thermoelectric properties of cubic phase SnTiO3 employing first-principles calculation are examined. The calculations of all parameters via various potentials such as LDA, PBE-GGA, WC-GGA, PBEsol-GGA, mBJ-GGA, nmBJ-GGA, and HSE are performed. The computed band structure yields an indirect bandgap of 1.88 eV with the HSE approach. The optical parameters have been evaluated through absorption, dispersion, and loss function. For cubic phase SnTiO3, the maximum absorption coefficient α(ω) is 173 × 104 (cm)−1 at high energy region 9 eV. The thermoelectric properties of the SnTiO3 have been explored by the Seebeck coefficient, thermal conductivity, and power factor employing the BoltzTrap code with temperature and chemical potential. Furthermore, the thermodynamic quantities under high pressure (0–120 GPa) and temperature (0–1200 K) are also calculated.

Objective: This study was conducted to assess the gross morphological changes in abruptio placenta and its demographic prevalence in our set up. Study Design: A case control study. Place and Duration of Study: The study was conducted in Anatomy Department of Federal Medical and Dental College and data was collected from Gynaecology and Obstetrics department of Pakistan Institute of Medical Sciences, affiliated with Shaheed Zulfiqar Ali Bhutto Medical University (SZABMU) Islamabad in a duration of eight months from 13 July 2015 to 20 February 2016. Materials and Methods: Eighty pregnant women presented in the term pregnancy, forty having abruptio placenta, and forty with normal placenta already diagnosed by ultrasounds. Non-purposive sampling technique was done for the comparison between two groups. An organized data collection check list was used for the collection of data. The data was statistically analyzed using SPSS version 20 and MS Excel. The Chi-Square test and Student T test were applied, with p value ≤0.05. Results: During the study period, eighty pregnant women with forty abruption placenta cases were included. Among these most frequent age was 26 to 30 years (50%) with mean± SD age of 28.1± 4.9. Majority, 70% were of low socioeconomic status and mode of delivery was C-Section (87.5%) in abruptio placenta group. The mean weight (grams) of abruptio placentae was found to be 396.4 ±49.9 as compared to 523.3 grams + 38.8 in normal placentae. The diameter (cm) of abruptio placentae was 13.0±2.9 as compared to normal placentae16.4 + 3.8.The number of cotyledons were reduced to 11.5±6.1 in abruptio placentae as compared to control 16.5 + 6.8. Conclusion: It is concluded that gross morphological changes in abruptio placenta include reduction in its weight, dimensions and number of cotyledon. Moreover, the demographics show that it is more prevalent in low socioeconomic women leading to high rate of Cesarean Section.