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Green technique or chemical co-precipitation technique has been employed to synthesize the MgZnFe2O3, CoZnFe2O3 and NiZnFe2O3 quaternary alloys nanoparticles. The structural properties are investigated by X-ray diffraction (XRD) to determine structural parameters and crystallite size. XRD peaks index numbers and intensities are varied with the atomic number. The study of morphology for the mentioned quaternary alloys nanoparticles is analyzed by scanning electron microscopy (SEM) to measure the grain size. The optical properties are investigated via ultraviolet–visible (UV–vis) and Fourier-transform infrared spectroscopy (FTIR) to reveal the changing of absorption, transmission, reflection and bandgap as the atomic number changes for verifying optical dielectric constant and refractive index models. The obtained results suggest that MgZnFe2O3, CoZnFe2O3 and NiZnFe2O3 quaternary alloys nanoparticles are very suitable for potential application in optoelectronics and antibacterial treatment.

Using state-of-the-art first-principles electronic-band-structure calculations alongside density functional theory, we investigated the structural, elastic, electronic, and magnetic properties of LiMnZ2 (Z = Se, Te) compounds with a trigonal structure. Initially, we determined the equilibrium lattice structure and atomic positions, which aligned well with experimental values. Ferromagnetism was shown to be more favorable than the non-magnetic state. The elastic constants, cohesive energies, and formation energies indicated that the studied compounds were mechanically stable in the experimentally determined trigonal lattice. The analysis of spin-polarized band structures and density of states revealed that both LiMnZ2 compounds exhibited perfect half-metallic characters. The total spin magnetic moment per formula unit adhered to the Slater–Pauling rule, being exactly 4 μΒ, mainly concentrated at the Mn atoms due to the strong spin polarization of the Mn d orbitals. We anticipate that our results will prompt further experimental and computational studies for the application of these layered materials in practical devices. [ABSTRACT FROM AUTHOR]

A comprehensive examination of the crystal structure, as well as elastic and thermal properties, of the recently created Zintl phase CsGaSb2 has been carried out using ab initio density functional theory pseudo-potential plane-wave calculations. All the provided facts presented are newly forecasted, with the exception of the structural properties under normal conditions. The calculated lattice parameters and interatomic bond lengths of the investigated material closely correspond to the actual values, indicating a high level of accuracy. Forecasts have been generated for the elastic parameters and related characteristics of both single-crystal and polycrystalline phases of CsGaSb2. The parameters encompassed in this list are elastic constants, shear modulus, bulk modulus, Poisson's ratio, Young's modulus, anisotropy indices, elastic wave velocities, Pugh's criterion, and Debye temperature. The mechanical and dynamic stability of CsGaSb2 as well as its elastic anisotropy have been established. The temperature dependence of various macroscopic properties, including bulk modulus, unit cell volume, volumetric thermal expansion coefficient, isochoric and isobaric thermal capacities, Debye temperature, Grüneisen parameter, and entropy function, was evaluated at specific pressures using Debye's quasi-harmonic approach in combination with ab initio calculations. [ABSTRACT FROM AUTHOR]

Intense UV emission is observed in Ce3+-doped GdBO3 nanophosphor, successfully prepared by simple sol gel method. The synthetized nano-powder sample is characterized by diffractometry (XRD) and room temperature steady photoluminescence. The XRD analysis shows that the crystallite size is 55 nm and crystallizes in the vaterite structure. The room temperature excitation and emission observed bands are assigned to 4f ↔ 5d inter-configurational transitions and investigated. First principal Density Functional theory DFT + U calculations, implemented in VASP code was used to performed the study of the structural and electronic structure of GdBO3:Ce3+ nanomaterial system in both vaterite P63/mmc and calcite R-3C. The U parameter is varied to give best 4f Ce position in GdBO3 bandgap. Also, it was found that the R-3C is the ground state crystalline structure and that the observed P63/mmc is higher in energy by about 0.1 eV/atom. By comparison between experimental and calculations results energy Ce3+ energy levels scheme relative to electronic band structure was constructed. [ABSTRACT FROM AUTHOR]

This study uses density functional theory calculations to study the impact of pressure on the structural, elastic, and thermodynamic properties of CaRh2P2 and BaRh2P2 compounds. The equilibrium structural parameters closely match the experimental values. CaRh2P2 shows a greater reduction in lattice parameter "a" under pressure, while BaRh2P2 shows the opposite trend. The single-crystal elastic constants calculated for both compounds meet the criteria for mechanical stability under varying pressures up to 18 GPa. The study extends to polycrystalline elastic properties, including bulk modulus, shear modulus, Young's modulus, Poisson's ratio, and related properties, under pressures up to 18 GPa. The Pugh ratio, Cauchy pressure, and Poisson's ratio indicate the ductile behavior of the title compounds. BaRh2P2 exhibits superconducting characteristics, unlike CaRh2P2, confirmed by interlayer PP bond length calculations. Debye's quasi-harmonic model explores the temperature dependencies of various properties, with results that align well with elastic constant data, thus validating the results. [ABSTRACT FROM AUTHOR]

In this work, first-principles computational study on the structural, electronic and optical properties of Tl4GeS3, Tl4GeSe3 and Tl4GeTe3 ternary compounds are presented. The computations are performed with pseudopotential plane wave method based on density functional theory with the generalized gradient approximation of Perdew–Burke and Enzerhof (PBE-GGA). The calculated structural, electronic and optical parameters are consistent with the available experimental results. The computed electronic band structures confirm the semiconducting nature for these compounds with direct band gaps of 0.17 eV, 0.085 eV and 0.015 eV for Tl4GeS3, Tl4GeSe3 and Tl4GeTe3, respectively. Furthermore, the electron charge density distribution indicated that the nature of bonds between Ge and S/Se/Te are covalent nature, whereas Ge and S/Se/Te anions formed ionic bonds. The optical parameters revealed that Tl4GeS3, Tl4GeSe3 and Tl4GeTe3 are highly dielectric materials and has the potential to be beneficial in the optoelectronic device applications. Keywords: Band gap, Density of states, Optical properties, Density functional theory

The benefits of the electrical-based biosensor include cheap production and fast response time of detecting diseases. An interdigitated electrode (IDE) is fabricated using silver (Ag) as a metal contact that is deposited on aliminium (Al) nanoparticles doped with both zinc oxide (ZnO) and Silicon (Si) forming AZO/Si nanostructures by vacuum coater in a thermal evaporator. The electrical properties are studied as a function of frequency and voltage using I–V characteristics. Sol–gel method under annealing temperature, 500 °C is utilized to generate Al nanoparticles doped ZnO nanostructures. UV–vis spectrophotometer, Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM) and X-ray diffractometer (XRD) are used for analyzing optical, topographical, morphological and structural studies of AZO nanostructure, respectively. Specific empirical models of optical dielectric constant, bulk modulus and refractive index are also verified. PACS: 75.75.Fk, 77.55.hf, 87.85.fk, 88.10.gp, Keywords: AZO, Sol–gel method, Characterization, Optical

The present work is a theoretical study of the structural and spin-polarized dependent optoelectronic thermoelectric properties of the melilite-typeGd2Be2GeO7 compound, using the full potential linearized augmented plane wave approach in the framework of density functional theory. The predicted structural parameters are in good accordance with the measured counterparts. It is found that the title compound is more stable in the ferromagnetic order than in the non-magnetic order. The calculated band structure using the modified Becke–Johnson potential reveals that the studied compound has a wide bandgap of 3.78 eV. The frequency-dependent linear optical spectra are studied in an energy range expanding from 0 to 30 eV. Finally, the semi classical Boltzmann theory as incorporated in the Boltztrap code is used to study the spin-polarized dependent transport properties. The obtained results show that Gd2Be2GeO7 is a potential candidate for conversion energy device applications.