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HfO2 has allured the significant attention on account of its chemical and thermal stability, large bandgap value, high dielectric constant and refractive index, good transmittance values in ultraviolet and infrared bands establish it as a significant candidate for resistive switching oxide and optical materials. In the present work the effect of Ag ion beam with 120 MeV high energy treatment of HfO2 ALD grown thin films with thickness 40 nm is examined at distinct ion fluence from 1E12 to 1E13 ions/cm2. The present work reports the influence of 120 MeV Ag ion beam irradiation on the optical, structural and morphological characteristics of thin films grown by ALD method on glass and silicon substrate. The Tauc plots have been used to calculate the optical bandgap of films give the details of structure of films on account of slope of the plot is associated with the degree of the order in the network of bond. The SRIM simulation has been explored for the study of electronic and nuclear energy loss takes place in the samples. Structural analysis of pristine and ion beam irradiated thin films were studied by the X-ray diffraction technique. The effect of ion beam irradiation on the surface morphology were studied by the Atomic Force Microscopy (AFM), reveals that grain size rely on the variation takes place in the ion beam fluence. The ion beam causes surface state and interstitial defects in thin films samples as remarked by the Photoluminescence characterization method. Additionally, the RBS was used for the calculation of thickness of films. [ABSTRACT FROM AUTHOR]

The current work describes a biological method to create silver nanoparticles (AgNPs) using jojoba oil. As a reducing and capping agent, jojoba oil was utilized in the production of AgNPs. AgNPs may be classified by their UV-VIS, FTIR, and spectra. A transmission electron microscope (TEM) was used to examine the shape and size of the silver nanoparticles. The average size of the synthesized silver nanoparticles was 25.6 ± 10.3 nm, and they had a spherical shape. According to FTIR spectroscopy tests, the silver nanoparticles' surface had organic molecules bound to it. Five bacterial isolates were isolated and tested for pathogenicity on potatoes. All isolates produced the typical symptoms of soft rot disease. Isolate Pcc2 caused the highest disease severity (45%). According to 16sRNA, isolate Pcc2 was identified as Pectobacterium carotovorum subsp. carotovorum. Increasing the dosage of AgNPs increased the antibacterial effect against P. carotovorum. From these results, we can conclude that the use of AgNPs is a safe method for controlling postharvest potato diseases caused by Pectobacterium carotovorum subsp. carotovorum. [ABSTRACT FROM AUTHOR]

WO3 is considered to be significant for diverse applications such as gas sensing, photocatalysts, and photovoltaic devices because of its optical wide band gap. Ion beam treatment of various metal oxides produces defects that modify various properties such as topographical, structural, and optical characteristics of the metal oxides. When the energetic ion pass through the target materials, it causes two kinds of energy losses, i.e., nuclear and electronic energy loss. In low-energy ion beam treatment of thin films, nuclear energy loss dominates over electronic energy loss. In our current study, thin films of tungsten oxide were grown on substrates of glass and silicon by the RF-sputtering method. The sputtered WO3 thin films were exposed to an ion beam of Au iosn with an energy of 80 keV at various fluences of 5E14 ions/cm2, 1E15 ions/cm2, and 5E15 ions/cm2. Atomic force microscopy (AFM) shows that, after implantation, enhancement in grain size was observed from 49.5 nm to 56.6 nm. The optical study displays the alteration in the energy band gap of ion-implanted WO3 thin films from 2.75 eV to 2.99 eV. From Raman spectroscopy, the phase observed is monoclinic for virgin and implanted samples. PL spectroscopy of virgin and ion beam-implanted WO3 thin films shows emission spectra at the wavelength of 580 nm at an excitation wavelength of 420 nm. X-ray photoelectron spectroscopy shows the appearance of tungsten and oxygen atoms and shows the electronic structure variation after Au ion beam implantation. [ABSTRACT FROM AUTHOR]

The advancement of crystalline growth and characterization tools allows us to investigate novel nonlinear optical substances suitable for photonic applications. Bis-(4-aminopyridine)-zinc(II) acetate (B4AZA), a metal–organic crystal was produced in this study using the slow evaporation procedure at room temperature. Analytical studies such as X-ray crystallography, Fourier transform infrared (FT-IR), UV–visible (UV–Vis), fluorescence, second harmonic generation (SHG), and dielectric tests were used to characterize the as-grown B4AZA crystals. According to the solubility data, the sample has a positive temperature coefficient of solubility. The crystallographic findings show that the B4AZA crystallized in a monoclinic structure with the P21/n space group. Molecular vibrations and functional groups in the substance were determined using the FT-IR technique. The UV–Vis absorbance and transmittance spectra have shown the wide transparency and minimum absorbance of the B4AZA in the near UV and entire visible regions of the electromagnetic spectrum. The bandgap of the B4AZA has been calculated using the Tauc relation and found to be 4.32 eV. The fluorescence spectra have shown a prominent emission peak at 584 nm with an excitation wavelength of 280 nm. The larger Stokes shift found in the fluorescence spectra is advantageous for practical applications. The SHG study revealed that the powdered B4AZA samples generated a second harmonic output. The dielectric test revealed frequency-dependent changes in the dielectric constant and loss factor. Both the dielectric constant and the loss factor decrease exponentially as frequency increases, reaching low values at higher frequencies. The experimental results illustrate the suitability of the B4AZA crystals for photonic applications. [ABSTRACT FROM AUTHOR]

Silver nanoparticles can be produced by an array of procedures, such as chemical, physical, and biological processes. The process of biosynthesis is more economical and significantly more environmentally friendly. We describe an environmentally compatible method (biosynthesis) of producing silver nanoparticles (Ag: NPs) with the capping component Artocarpus heterophyllus in this research work. Powder-X-ray crystallography (P-XRD), Fourier Transform Infrared (FT-IR), UV–visible (UV–Vis), Photoluminescence (PL), Field emission scanning electron microscopy (FE-SEM), and an antimicrobial test were all used to examine the synthesized samples. The P-XRD analysis revealed that the produced NPs have an FCC form with a typical particle size of 23 nm. FT-IR spectra further demonstrate the availability of the functional groups in the synthesized nanoparticles. The absorbance and transmittance spectra of the UV–Vis study have shown substantial transparency and less absorbance of the Ag: NPs in the entire visible region. The bandgap of the Ag: NPs was found to be 3.25 eV using the Tauc relation. In the PL study, an emission peak at 472 nm was found, suggesting the fluorescence emission of Ag: NPs. The FE-SEM micrographs provide confirmation of the surface-wide aggregate of nanostructural homogeneities. The FE-SEM micrographs illustrate that Ag: NPs are homogeneous aggregates of very small spheres. Variations in particle size and surface area-to-volume ratios of synthesized NPs have been proven to be responsible for the antibacterial activities. According to the antibacterial study, Ag: NPs restrain the development of both normal and harmful bacteria and so have the potential to be utilized for coating surgical equipment for aseptic operators in the healthcare industry. [ABSTRACT FROM AUTHOR]

In this study, homogeneous NiO particles on ZnO heterojunction were incorporated with the objective of scrutinizing its probable applications in antifungal processes. Advanced instruments were engrossed to determine the phase identification, elemental composition, and particle discrepancy of the synthesized material. The electrochemical impedance response was pondered using Nyquist diagrams to accredit an equivalent circuit and extract fundamental circuit parameters. The Z″ versus Z′ plot plugged a semicircular shape, broaching the presence of heterogeneous or broad relaxation processes. The antifungal efficacy of the homogeneous NiO on ZnO heterojunction was appraised against various fungi species, including Aspergillus Niger, Aspergillus flavus, Rhizopus microspores, and Pencillium sp., at a concentration of 20 µl. These results accentuated the versatile applicability of the studied material. [ABSTRACT FROM AUTHOR]

Here, ultrasonic spray pyrolysis method (USP) was utilized to produce pure and silver doped copper oxide nanostructures on glass substrates. Thereafter, several characterization techniques were conducted on the grown samples to delve into their morphological, structural, electrochemical, and optical aspects. The mentioned analyses were carried out by performing x-ray photoelectron spectroscopy, scanning electron microscope, X-ray diffraction, electrochemical impedance spectroscopy, galvostatic charge-discharge, cyclic voltammetry, and UV–visible spectroscopy measurements. Thus, the impact of silver impurity doping on the relevant aspects of host material were recorded as well as the features of unspoiled copper oxide films. Accordingly, the samples, as indicated by X-ray diffraction results, possessed (002) preferential plane orientation of copper oxide material along with the crystallite sizes ranging from 52.52 nm to 75.02 nm due to the imperfections caused by the silver doping. The scanning electron microscope images exhibited that the silver doping did not form significant modifications in the host material morphology where nanowire-like structures observed. The presence of the suggested materials in the films was verified by the x-ray photoelectron spectroscopy. Also, the UV–visible spectroscopy measurements detected that optical absorbance edge and bandgap energy values red shifted as a result of the impurity doping. The electrochemical supercapacitors performances of the silver doped copper oxide nanostructured thin films were inspected by using the GCD, EIS, and CV. The silver doped copper oxide films demonstrated a specific capacitance value of 66 F/g at a current density of 1 A/g in 1 M KOH electrolyte. From Nyquist plot, Rs, Rcor, Rpo, Ccor and Cc were obtained as 2.327 × 103 Ω.cm2, 43.63 × 103 Ω.cm2, 4.580 × 103 Ω.cm2, 111.5 × 10-6 S*s^a. cm-2 and 101.1 × 10-6 S*s^a. cm-2, respectively. The results indicated that the electrochemically synthesized the silver doped copper oxide electrodes can be obtained and developed as an alternative electrode material for supercapacitors (SCs). [ABSTRACT FROM AUTHOR]

Non-linear optical materials have greatly impacted science and technology in recent years. In the present work, crystals of amino acid derivative l-histidinium acetate dihydrate (L-HA) were grown using the gradual evaporation method. The powder-crystal X-ray diffraction (PXRD) technique was applied to examine the phase composition of the crystal sample. The XRD analysis showed that the L-HA was crystallized into the triclinic system. Microstructural parameters were evaluated, including dislocation density and micro-strain induced in the samples. The vibrational modes of the L-HA crystal were found using confocal Raman spectrum analysis. UV–Vis spectral analysis was applied to ascertain the crystal's optical absorbance and transmittance. The bandgap and Urbach edge of L-HA were explored in the UV–Vis spectrum. The second harmonic generation potency of L-HA was examined using Kurtz–Perry analysis, and it was found that L-HA exhibited significant SHG efficiency. The dielectric and impedance characteristics of the L-HA were assessed in the 100 Hz‒5 MHz range at different temperatures. Dielectric measurements show that at frequencies higher than 10 kHz, the dielectric constant and dielectric loss are saturated at minimum levels. The Nyquist graph displays the negative temperature coefficient of resistance in the compound. Vickers microhardness analysis demonstrates the normal indentation size effect and hard nature of the L-HA sample. Thus, the L-HA crystals are suitable for optoelectronic applications due to their excellent optical characteristics, considerable SHG efficiency, and appropriate dielectric, impedance, and microhardness features. [ABSTRACT FROM AUTHOR]

In this work, poly(p-aminophenol), a conductive polymer, was synthesized via chemical polymerization from the monomer of p-aminophenol in a basic aqueous medium using ammonium persulfate as the initiator. The polymer's properties were assessed using ultraviolet-visible spectroscopy, fourier transform infrared, thermogravimetric analysis, scanning electron microscope, and X-ray diffraction methods. The fourier transform infrared results show a peak such as the robust signal at 3126 cm–1, corresponding to O–H vibrations associated with phenoxide ion existence in the polymer. The presence of N–H stretching vibration of an aromatic amine was affirmed by the peak at 2989 cm–1. The presence of a strong, broad peak at 2θ of 17.52° indicated amorphous behavior in poly(p-aminophenol). The weight loss was shown at 87, 276 and 517°C due to moisture removal, anion removal, and the degradation of polymer. Scanning electron microscopy showed sphere-like particles in poly(p-aminophenol) surface morphology. The electronic properties of poly(p-aminophenol) were investigated using quantum chemical calculations at the density functional theory level of theory. Density functional theory calculations were performed using two functionals, namely B3LYP and wB97XD, in combination with the 6-311+G(2d, p) basis set. These calculations aimed to determine various quantum chemical parameters, conduct natural bond orbital analysis, assess topological parameters, investigate nonlinear optical properties, and evaluate thermal properties. This approach balanced computational efficiency and accuracy to investigate reactivity, stability, charge transfer, optical properties, and thermal behavior. The calculations revealed significant changes in the reactivity and stability of the studied compound as it transitioned from the non-protonated to the protonated state, analyzed in both the gas phase and various aqueous environments. Furthermore, the presence of strong hydrogen bonds and limited nonlinear optical potential suggest the material may be suitable for applications beyond nonlinear optics. Additionally, the calculations explored static thermodynamic properties, including heat capacity, entropy, and enthalpy, highlighting their temperature-dependent behaviors. Poly(p-aminophenol) has excellent thermal stability and robust hydrogen bonding. However, its low nonlinear optical potential indicates its usefulness for uses other than nonlinear optics. [ABSTRACT FROM AUTHOR]

To solve environmental-related issues (wastewater remediation, energy conservation and air purification) caused by rapid urbanization and industrialization, synthesis of novel and modified nanostructured photocatalyst has received increasing attention in recent years. We herein report the facile synthesis of in situ nitrogen-doped chemically anchored TiO2 with graphene through sol–gel method. The structural analysis using X-ray diffraction showed that the crystalline nitrogen-doped graphene-titanium dioxide (N-GT) nanocomposite is mainly composed of anatase with minor brookite phase. Raman spectroscopy revealed the graphene characteristic band presence at low intensity level in addition to the main bands of anatase TiO2. X-ray photoelectron spectroscopy analysis disclosed the chemical bonding of TiO2 with graphene via Ti–O-C linkage, also the substitution of nitrogen dopant in both TiO2 lattice and into the skeleton of graphene nanoflakes. UV–Vis absorption spectroscopy analysis established that the modified material can efficiently absorb the longer wavelength range photons due to its narrowed band gap. The N0.06-GT material showed the highest degradation efficiency over methylene blue (MB, ∼98%) under UV and sulfamethoxazole (SMX, ∼ 90.0%) under visible light irradiation. The increased activity of the composite is credited to the synergistic effect of high surface area via greater adsorption capacity, narrowed band gap via increased photon absorption, and reduced e−/h+ recombination via good electron acceptability of graphene nanoflakes and defect sites (Ti3+ and oxygen vacancy (Vo)). The ROS experiments further depict that primarily hydroxyl radicals (OH•) and superoxide anions (O2•−) are responsible for the pollutant degradation in the process redox reactions. In summary, our findings specify new insight into the fabrication of this new material whose efficiency can be further tested in applications like H2 production, CO2 conversion to value-added products, and in energy conservation and storage. [ABSTRACT FROM AUTHOR]

The composition of the water-extractable organic matter (WEOM) of sedimented soils, namely, dark-humus water-accumulative stratozems (Fluvic Chernic Phaeozems (Loamic, Pachic)) in the nonplowed bottom of a dry valley is studied and compared to the WEOM composition of arable soils (Haplic Chernozems and Fluvic Chernic Phaeozems (Loamic, Pachic)) on the adjacent cropland of a small catchment. The WEOM composition of stratozems is examined layer by layer from the surface to the depth of 120 cm with a step of 20 cm. Water extracts are analyzed for organic carbon, nitrogen, and pH. The optical properties of WEOM are analyzed by spectrophotometry and fluorescence spectroscopy and compared in these soil types. The specific features of the changes in the properties of stratozems with the depth are also analyzed. The erosion and accumulation processes are shown to considerably influence the composition of soil WEOM. However, the content of dissolved carbon in WEOM does not significantly differ either between arable chernozems and sediments or down along the vertical profiles of the sediments on dry valley bottom. In turn, the content of nitrogen in the WEOM of arable chernozems is generally higher as compared with that in sediments, where it predictably decreases with depth. Presumably, the decrease in the nitrogen content of WEOM in sediments with depth is associated with its uptake by plant roots and an increase with depth in the share of anaerobic zones, with their activated denitrification processes. The top 0–60-cm soil layer in sediments actively retains the nutrients leached from arable soils, primarily, dissolved nitrogen. This process promotes the carbon accumulation in the underlying layers. An increase in the content of total organic carbon in Fluvic Chernic Phaeozem (Loamic, Pachic) layers below 60 cm is explainable with the accumulation of the dissolved organic matter migrating downward. On the one hand, the dissolved organic matter is sorbed by soil and, on the other hand, is preserved as a result of a decrease in the microbial activity caused by the deficiency in nutrients. [ABSTRACT FROM AUTHOR]

K Zr 2 PO 4 3 : xEu 3 + Nanophosphors with varying molar percentages (0.5, 1, 2, 3, 4, and 5 mol. %) are synthesized using a urea-assisted solution combustion synthesis approach. The phosphors exhibit crystallization in a rhombohedral phase, namely in the R 3 ¯ c space group with the help of X-ray diffraction. The anionic group of (PO4)3− is responsible for all the vibrations occurring in the FTIR spectra. The photoluminescence characteristics of K Zr 2 PO 4 3 : xEu 3 + (x = 0.5 – 5 mol. %) are examined when excited at a wavelength of 392 nm, resulting in the prominent emission at 613 nm. At a concentration of 2 mol. %, the optimal concentration is observed, and the emission tone of the phosphor is centered in the reddish part of the color gamut, with a high color purity of 92%. It is observed that the synthesized phosphor has a branching ratio more than 50%, indicating a possible laser emission transition. The band gap energy of K Zr 2 PO 4 3 : Eu 3 + is found via diffuse reflectance measurements and found to be 4.19 eV. The value of metallization criteria is less than unity which dictates the non-metallic nature of the synthesized phosphors. These results indicate that this phosphor is very suitable for use in solid-state lighting applications as a red light-emitting phosphor. [ABSTRACT FROM AUTHOR]

This study examines the impact of thermal annealing on ZnO nanorods produced by vapour phase transport. Nanorods were annealed at temperatures of 300, 500, and 700 °C. It has been demonstrated through X-ray diffraction that the annealing process led to an increase in crystalline size from 34 to 51 nm, indicating improved crystallinity. The optical bandgap decreased from 3.28 to 3.22 eV as a result of defect minimization during annealing. Due to increased crystallinity and fewer defects, annealing increased the dark conductivity from 0.8 to 2 S/cm, as shown by electrical experiments. After annealing, the photosensitivity increased from 10 to 35 and the responsivity rose from 0.18 to 0.48 A/W. The quantitative results demonstrate that annealing modifies the physical properties of ZnO nanorods and improves their photodetection capabilities. [ABSTRACT FROM AUTHOR]

Dissolved organic matter is the most mobile part of soil organic matter; however, its change and transformation occurring during soil erosion are insufficiently studied. We assess the optical properties of water-extractable organic matter (WEOM) in arable soils with different degrees of degradation caused by erosion and sedimentation in a small arable catchment in the Kursk oblast, namely, the WEOM of arable Haplic Chernozems (noneroded and moderately eroded) and their analog with soil matter sedimentation, Fluvic Chernic Phaeosem (Loamic, Pachic). WEOM is isolated from the aggregates of 2–1 mm and >10 mm. In water extracts, the contents of organic carbon and nitrogen were measured. Optical properties were assessed according to absorption spectra and three-dimensional fluorescence spectra. The eroded and aggraded soils emerge to be similar to each other but significantly differ from noneroded chernozem in terms of the main quantitative characteristics of soil organic matter—the content of organic carbon and nitrogen, and pH. However, both the quantitative and qualitative WEOM characteristics show a different trend: the WEOM of Fluvic Chernic Phaeosem (Loamic, Pachic) significantly differs from eroded and moderately eroded Haplic Chernozems. In addition, some characteristics of WEOM (nitrogen content, SUVA254, S350–400, and SR) depend on the size of the aggregates from which WEOM is isolated (2–1 or >10 mm). The fluorescent properties of WEOM also depend on the size of the aggregates. Our data suggest that the properties of the WEOM in a small arable catchment of the central forest-steppe zone are variable and are largely determined by the destruction of water-unstable aggregates and consolidation of their particles, as well as by the leaching of dissolved organic matter. When aggregates are destroyed by water, their particles migrate with flows along the slope, and organic matter is decomposed. However, particles accumulate in depressions to become consolidated into blocky structural units, while the properties of soil WEOM are significantly altered, both due to degradation of organic matter and as a result of its leaching. [ABSTRACT FROM AUTHOR]

Context: Xanthates are organic compounds of great interest in coordination chemistry due to their different basic sites, which allow them to form complexes with different coordination modes and geometries. These compounds are relevant in the environment and act as heavy metal collectors in aqueous environments. In this theoretical–experimental work, electronic spectroscopy studies of n-propyl xanthate complexes with group 12 metals were performed. This study verified structural differences in these systems, depending on the environment in which they are inserted. In addition, structural differences were observed when the solid was changed to an n-hexane solution. Thus, it was observed that the complexes assume a mononuclear structure in solution, while they present a polymeric form in the solid phase. The electronic spectra obtained through TD-DFT calculations were compared to those of the previously synthesized complexes. In the final theoretical analysis, the main orbitals involved in these transitions were assigned using population analysis calculations. The synthesis of the complexes was confirmed through infrared (MID and FAR), UV‒Vis, Raman, and NMR-1H spectroscopic analyses. Methods: The structures of the mononuclear and polymeric complexes were optimized in vacuum and n-hexane. Under vacuum, DFT levels M06L/6–311 + + G** + LANL2TZ and M06L/def2-TZVP were used for the mononuclear complexes, and M06L/LANL2DZ + LANL2 were used for the polymer complexes. For the calculations of the mononuclear complexes in n-hexane, the same level of theory was used for the solid state. TD-DFT calculations for 300 excited states were performed with the same levels of theory and used the optimized structures of the complexes. Furthermore, population analysis was carried out on all the systems studied. Gaussian 09 software was used for the structure optimization, TD-DFT, and population analysis calculations. GaussSum software was used to evaluate the molecular orbitals and electronic spectra. [ABSTRACT FROM AUTHOR]

Molybdenum Trioxide nanoparticle (MoO3-NPs) was introduced to Cellulose acetate (CA) biopolymer with different concentration using casting process by dispersed MoO3-NPs [0.0, 0.25, 0.5 and 1.0 wt%]. Molecular structure of samples has been studied using XRD and UV–Vis. the data shown by X-ray results indicated the amorphous nature of the pure polymer. Some peaks are appeared as a result of the addition of MoO3-NPs which indicate that samples were partially crystallized. The crystallite size of nano-metal oxide was calculated for blended samples by Size–Strain Plot method which was found to increase with increasing the concentration of MoO3. UV–Vis results indicate that there exist two indirect energy band gaps; Onset band gap which observed to decreases from 1.3 eV for pure polymer to 0.78 eV for polymer blended with 1.0 wt% MoO3-NPs and HOMO–LOMO band gap which observed to decrease from 3.23 eV for pure polymer to 2.89 eV for polymer blended with 1.0 wt% MoO3-NPs. This indicate that the addition of nano-metal oxide improve the optical conduction of CA. Urbach energy was observed to increase with increasing MoO3-NPs from 0.27 eV for pure CA to 0.32 eV for 1.0 wt% MoO3-NPs concentration which may be occurred due to the creation localized states at the band gap as a result of the addition of MoO3-Nps. [ABSTRACT FROM AUTHOR]

When the monochromatic light passes through a random attenuating medium, the radiant intensity drops exponentially with the length of the path and attenuation coefficient. The law of exponential decay was called the law of Bouguer, Lambert, Beer or some combination of these three. Here we refer to it as the modified Beer–Lambert law due to the arrangement proposed in the current work. This work aims to use UV–Vis spectroscopy and apply Beer–Lambert law; the feasibility of the work is assessed and shows the possibility of validating a beam intensity measurement experiment in two experimental situations with a known constant. The empirical part of the work consists of changes in chemical or physical properties. The first experimental situation consists of the variation of the concentration of the medium and evaluates the absorption of the laser beam. In this situation is used industrial synthetic dye. The second experiment also assessed the absorption of laser intensity, using variations of the number of films poly (ethylene terephthalate) polymeric sums found in the PET bottle. The values found for constant were ≈ 2.697 in the variation of concentration of synthetic dye in blue color, and for the condition of PET, films were found and ≈ 2.699. The value of the constant experimentally found approaches the Euler number. And they are so, proving that the Euler number can be determined experimentally in a system of Markovian non-interagent particles and how to experimentally validate a result by the association of a constant known in the literature. [ABSTRACT FROM AUTHOR]

The melt-quenching method was used to manufacture newly synthesized glasses with a nominal composition of 60B2O3 – 20CaO – 15ZnO – 5Li2O – xEu2O3: 0 (Eu-0.0) ≤ x ≤ 0.5 (Eu-0.5) mol%. The structural, physical, FTIR, UV–visible spectra, and mechanical properties of the synthesized Eu-x glasses are examined. XRD results verified the amorphous condition of proposed glasses. The density (ρ) of the prepared glasses increased from 3.231 to 3.338 g cm−3, but in contrast, the molar volume (VM) decreased from 20.643 to 20.506 cm3 mol−1 with increasing Eu3+ ions. FTIR spectroscopy illustrated absorbance peaks appear around 393 and 464 nm, which indicates the presence of electronic states in the wide band gap of glass matrix. These peaks are attributed to the 5L6 and 5D2 electronic states of Eu3+ ions. UV–visible measurements showed an improvement in optical absorbance and a decrease in optical energy gap. The Eu3+ ions mol% doping into the proposed glasses results in generating photoluminescence glasses, which is attributed to the 5D0 → 7F1, 5D0 → 7F2, 5D0 → 7F3, and 5D0 → 7F4 electronic transitions of Eu3+ ions. Thus, the emission spectra due to the 393 nm excitation results in the appearance of emission peaks at 593 (orange), 617 (strong red), 653 (red), and 698 (red) nm. The Poisson's ratio (σ) of Eu-x glasses is decreased from 0.3927 to 0.3903 as the molar fraction of Eu3+ ions is increased from 0.0 to 0.5 mol%. The thermodynamic properties of the glassy network are hidden in the Gibbs free energy (G) which started at 33.56 and ended at 33.72 kJ.cm−3 at low and high Eu3+ ions content mol%. Furthermore, all elastic moduli increased linearly with molar increment of Eu3+ ions in the molecular structure of the proposed glassy network. [ABSTRACT FROM AUTHOR]

The analysis to plan for high-efficiency with affordable molecules such as coumarin, prop-1-ene with 2-cyano-N-hydroxyacrylamide (A1), 2-cyanoprop-2-enedithioic acid (A2), 1-cyanovinylphosphonic acid (A3) and 1-cyanoethenesulfinic acid (A4) are one of the most important aspects of improving the non-linear optical (NLO) property besides dye-sensitized solar cells (DSSCs) applications. NKX-2311 has been taken as a literature molecule, it contains coumarin as a donor moiety (D), prop-1-ene as a π-spacer (π) and cyanoacrylic acid as an acceptor moiety (A). The three fragments that make up the D-π-A structure. The family of A1-A4 metal-free organic coumarin NKX-2311 dye derivatives have examined for applications involving optoelectronics in this research. Density functional theory (DFT) and time-dependent DFT (TD-DFT) techniques utilizing quantum chemical calculations, the molecular electronic structures, ultra-violet visible (UV–Vis) absorption, transition density matrix (TDM), electron–hole mobilities (reorganization energies) and photovoltaic (PV) characteristics of the A1-A4 sensitizers have been calculated. For optoelectronic devices, the effect of chemical alteration on the UV–Vis spectra about PV parameters of the NKX-2311 were illustrated. The performance of hybrid functionals such as B3LYP, CAM-B3LYP and ωB97XD was assessed to compare with the absorption wavelength of NKX-2311. The B3LYP method and NKX-2311 have had a superior fit based on the selected functionals. Consequently, the B3LYP/6-31G(d) theory has been used to study the excited state computations of A1-A4 dyes at UV–Vis wavelengths. The findings demonstrate that A2 dye has a smaller energy gap and that UV–Vis spectra were constantly redshifted. According to the computational outcomes, the A1-A4 sensitizers can respond positively to the processes of dye regeneration and electron injection based on their lowest unoccupied and highest occupied molecular orbitals (LUMOs and HOMOs), respectively. A2 dye has the greatest hole mobility due to its lowest λ + value of 0.1701 eV, while A1 dye has extreme electron mobility due to its lowest λ - value of 0.2273 eV. The NLO property of molecules A1-A4 has been calculated by two ways such as polarizability and first-order hyperpolarizability. The most promising candidate for NLO performance has been identified as the dye with computed values of A2. The results would serve as a useful resource for any upcoming demands and also more advantageous for obtaining optoelectronic applications. [ABSTRACT FROM AUTHOR]

In this communication, the preliminary structural analysis, high-resolution Raman spectra, optical band gap, and magnetization have been studied in polycrystalline sample of (BiFeO3)1-x(SmFeO3)x (BFO–SFO); (with x = 0.0, 0.1, 0.2, and 0.3) ceramics. The X-ray structural analysis confirmed the formation of single phase with rhombohedrally distorted perovskite structure of the materials. The crystallite size of the materials decreases with increasing SmFeO3 contents in BiFeO3. Raman spectroscopy indicates 13 active phonon modes corresponding to (BiFeO3) rhombohedrally distorted R3c structure. The band gap of the studied materials decreases from 2.27 to 2.02 eV which may be due to the restructuring of molecular orbitals. The photocatalytic behavior of the materials is improved as a result of these findings. Substitution with SmFeO3 on BiFeO3 will enhance the ferromagnetic properties of the materials. [ABSTRACT FROM AUTHOR]

Fiber optic-based Raman and UV–Vis spectroscopy systems were commissioned for use in an inert atmosphere for in situ analysis of high temperature molten salts. The speciation of samarium chloride was studied in the LiCl–KCl eutectic system at 500 °C. Raman and electronic absorption spectra indicated trivalent samarium forms an octahedral SmCl63− complex with two detectable Raman features. Metallothermic and electrolytic reduction of Sm(III) to Sm(II) in the alkali halide solution was carried out to investigate the coordination of Sm(II) in the same eutectic salt. Formation of the Sm(II) was confirmed using UV–Vis absorption spectroscopy. The resulting spectra are reported and discussed in terms of complex formation, inelastic scattering, and electronic absorption of the reduced Sm(II) ions. The Raman spectrum of metallothermically produced Sm(II) exhibited similar shift to the Raman spectrum of metallothermically reduced Nd(II). [ABSTRACT FROM AUTHOR]

Computational studies based on Density Functional Theory (DFT) and time-dependent DFT (TD-DFT) were used to determine molecular and thermodynamic parameters, optoelectronic and electronic properties, as well as chemical descriptors, UV–vis spectra and nonlinear optical response of the chromophores of 2-Styrylquinoline (M01) and 2-(3-nitrostyryl)quinoline (M02). We evaluated the impact of the substitution of the hydrogen atom in M01 by the nitro group (NO2) to obtain the molecule M02. The results show very good optoelectronic properties with respect to very high electric fields of the order of 1.43 × 109 Vm−1 for M01 up to 5.26 × 109 Vm−1 for M02. The energy gap decreases from 3.94 eV for M01 to 3.56 eV for M02; which suggest that they are semiconductors. In addition, these two molecules exhibit ionization potential (IP) and electron affinity (EA) quite close to those of Alq3 and could therefore be good candidates for the manufacture of Organic Light-Emitting Diodes (OLED). The chemical descriptors were assessed and allowed us to discuss the stability and reactivity of our molecules. Thus, the addition of the nitro group to the virgin 2-Styrylquinoline decreases the reactivity and stability of the 2-Styrylquinoline. The analysis of the IR and Raman vibrational spectra shows several peaks between 100 cm−1 and 3200 cm−1 of which the most intense for the molecule M01 are attributed to the stretching mode of the C–H bond in the phenyl ring and the C=C double bond in the quinoline ring. For the M02 molecule, stronger peaks were assigned to the stretching mode of the O–N and N–C bonds. The analysis of the UV–vis spectra showed that the maximum absorption wavelength of M01 is 334.80 nm and that of M02 is 375.37 nm; both located in the ultraviolet. The high values of first ( β T ) and second ( γ ¯ ) hyperpolarizability showed that both molecules have very good nonlinear optical properties and thus can be used for second and third harmonic generation. [ABSTRACT FROM AUTHOR]

Context: In this work, the 4-dimethylaminopyridinium-2,4-dinitrophenolate (4DMAP + 2,4DNP) by slow evaporation solution growth method has been presented. The Fourier transform infrared (FT-IR) (4000–400 cm−1) and FT-Raman (4000–50 cm−1) spectra were recorded for the grown crystal. Methods: The computational calculation has been carried out with density functional theory (DFT) in ground state with Gaussian program package. Optimized geometrical parameters (bond distances, bond angles, and dihedral angles) have been obtained and compared with X-ray crystallography data. The calculated fundamental vibrational frequencies from DFT/B3LYP with 6–311 + + G(d,p) level of theory were scaled so as to agree with the observed results, and the scaling factors were reported. Results: Experimental and computed ultraviolet–visible (UV–Vis) spectra in acetone and methanol solvents were found comparable to each other. Furthermore, the frontier molecular orbitals (FMOs) energies, molecular electrostatic potential (MEP), nonlinear optical (NLO), hirshfeld surface (HS), and global chemical descriptors of the molecule were also calculated. The thermal stability and the melting point of the title compound were analyzed by the thermogravimetric analysis/differential thermal analysis (TGA/DTA) techniques. The mechanical behavior of the organic single crystal was measured by Vickers micro-hardness method. The third-order nonlinear optical properties such as nonlinear refractive index (n2), nonlinear absorption coefficient (β), optical nonlinear susceptibility Reχ(3), and optical nonlinear susceptibility Imχ(3) were calculated by using the open and closed aperture Z-scan technique. Conclusion: The theoretical and experimental NLO values clearly proposed that the nonlinearity of 4DMAP + 2,4DNP molecule could be helped as a potential candidate for optical limiting, frequency doubling, and optical switching applications. [ABSTRACT FROM AUTHOR]

Many studies have demonstrated the effectiveness of various plant extracts in the synthesis of silver nanoparticles. The phytochemical components of plant extracts contain biodegradable agents necessary for the stabilization and synthesis of nanoparticles. However, extracellular components of microorganisms have been shown to have similar activity in recent years. This study expects nanoparticle synthesis using silver nitrate using bacteria from different plant and soil parts in the Proteobacteria and Actinomycetes families in the endophytic and free form obtained from various sources, determining their antimicrobial properties on other pathogenic microorganisms. Nanoparticules showed a positive effect on antibiotic-resistant human pathogenic bacteria (Staphylococcus, Escherichia, and Acinetobacter), two strains of the human pathogenic Candida, and six different plant pathogenic fungi (Aspergillus, Fusarium, Gaeumannomyces, and Penicillium) compared to the reference antibiotics and antifungals. The physical forms and dimensions of the nanoparticles were determined by XRD, FTIR, UV–vis, and scanning electron microscopy. We believe that our findings will be the basis for the bacterial nanoparticle production procedures. [ABSTRACT FROM AUTHOR]

Glycine magnesium chloride (GMC), a semiorganic hybrid crystal, and the coumarin dye were combined in an innovative way. As an outcome, the slow volatilization method was used to create the seed crystals of coumarin-doped GMC. The gained seeds underwent additional processing in order to recrystallize and produce high-quality single crystals without impurities. Due to its NLO (nonlinear optical) features, this semiorganic hybrid crystal offers a wide range of potential uses in electronics, optical devices, and other fields. In order to examine the optical activity and electronic characteristics of the coumarin-doped glycine magnesium chloride (CDGMC) molecule at the molecular level, they are combined. Synchrotron X-ray diffraction was used to analyse the structural characteristics of grown CDGMC, and FTIR, UV–VIS, and other optical examinations were conducted experimentally. The compound structure of CDGMC was built up and optimized in Gaussian 09w program using the basis set of DFT/B3LYP/6–311/G (d,p) at ground state with singlet spin, and the results were verified by visualizing in Gauss View. For efficient material conformation and compound identification in CDGMC, Fourier transform infrared (FTIR) spectroscopy was employed, along with frequency calculations for the generation of IR spectra. In order to compare the stimulated spectra at TD-DFT to the absorbance characteristics of the material used in the hybrid creation of CDGMC, UV–VIS spectroscopy is used. The electric and optical potential of the CDGMC structure is shown by molecular electrostatic potential, frontier molecular orbitals, Mulliken charge analysis, and natural bond orbital simulation techniques. For implementations in opto-electronic devices, dye-doped single-crystal CDGMC was effective in the study in terms of both observables and calculations. [ABSTRACT FROM AUTHOR]

In this article, we predict the optimized structures, the frequency analysis, and determinate quantum chemical descriptors, optoelectronic and electronic parameters; but also nonlinear optical (NLO), thermodynamic properties and Uv–vis absorption spectra of pristine dibenzo[b,def]chrysene (D0) and four of his derivatives obtained by lithium doping (D1, D2, D3, D4). The functionals DFT CAM-B3LYP and B3LYP with the 6–311 + + G(d,p) basis set was used to perform all the calculations. the results show that the doping has considerably reduced the gap energy from 2.879 eV for the pristine molecule D0 to 2.820, 2.698, 2.213 and 1.701 eV respectively for D1, D2, D3 and D4 with the DFT/B3LYP method, a clear improvement in conductivity and semiconductor properties thanks to lithium doping. These semiconductors properties suggest application of our new materials in conception of OLEDs and display devices. Calculated thermodynamic properties such as Gibbs free energy show that these molecules are thermodynamically stable. Doped molecules are very good optoelectronic materials according to very high electric field E values of 4.938 × 109 V m−1 and 4.723 × 109 V m−1 recorded in molecules D1 and D3. These derivatives of dibenzo[b,def]chrysene are also very good non-linear optical materials because of their first-order hyperpolarizability βmol which is greater in all the four cases than that of urea and para-nitro aniline (p-NA) which are references molecules in the non-linear optical domain. Our doped molecules are good candidates for NLO devices conception and realization. Moreover, the doping induces bathochromes effects which leads all our doped derivatives absorb in the visible domain and could be used in the manufacture of organic solar cells. [ABSTRACT FROM AUTHOR]

The hydrothermal method was used to prepare manganese oxide (Mn2O3) nanoparticles. Reduced graphene oxide (rGO) powder was sonicated with Mn2O3 forming a homogeneous Mn2O3-rGO nanocomposite. The prepared nanocomposite was characterized by UV–Vis spectroscopy to unravel origin of absorption photons strongly in the visible region that ensues due to charge transfer, Fourier transform infrared (FTIR) result reveal that the catalytic role of Mn2O3 in graphene reduction in sono-nano composites formation, X-ray diffraction (XRD) result also stand out all of structural parameters enhance slight increase for the position non-ideality (δ dislocation density) of atoms in crystallite size (D) and micro strain (ε).Decreasing the average crystallite size 41.13 nm and 37.2 nm for Mn2O3 and Mn2O3-rGO respectively due to high (600 W) ultra-sonication in presence of rGO-sheets. Field emission scanning electron microscopy (FESEM) show up uniform distribution of Mn2O3 and tightly anchored on the surface of the rGO sheets. These different characterization techniques confirmed the formation of the nanocomposite. Molecular quantum mechanical calculations for interaction investigation mechanism between rGO and Mn2O3, were conducted. Two model molecules were built for Mn2O3 and functionalized rGO, and 8 possible interaction mechanisms between Mn2O3 and functionalized rGO were proposed. Density functional theory (DFT) calculations using B3LYP/LANL2DZ basis set were conducted for the studied model molecules. Electronic properties and reactivity were investigated by calculating molecular electrostatic potential (MESP) mapping for model structures. The most active and plausible structure is the interaction of rGO through the OH group at the terminal with Mn2O3 through the Mn atom. It can be concluded that Mn2O3 activates the rGO surface and increases its detection sensitivity and reactivity. [ABSTRACT FROM AUTHOR]

This research attempts to synthesize an energy efficient and solar passive phosphosilicate based tint glass by doping with multi-metallic systems. The optimal infusion of minutely calibrated assimilation of metal oxides (Cu2O, CuO, Fe2O3 and SnO2) via conventional melt-quench-annealing route results in the formation of blue tint glass with excellent resistance in corrosive environment, and an appropriate density (~ 2.45 g/cm3). The amorphous structure of the glass even after annealing is confirmed by XRD analysis. FTIR study indicates IR vibrational bands related to the silicate matrix structural components. The metal oxide doping significantly improves the mechanical, optical and physicochemical properties of the synthesized tint glass, which has many applications in the building contractions. Optical properties of the tint glass measured by UV–Vis spectroscopy show that 28–44% visible transmittance for daylighting and 18–39% solar transmittance for heat gain into the building are achieved. The multi-metallic doping not only makes an excellent quality tint glass system that can reduce a significant amount of solar heat energy but also improves compressive strength, Young modulus and modulus of toughness. The glass also shows excellent chemical durability that suggests its applications in reducing air-conditioning loads and the cost of artificial daylighting in the modern buildings. This study leads to a pathway towards a possibility that the synthesized tint glass can be a suitable candidate for the commercial building envelope materials in certain rich daylight areas. [ABSTRACT FROM AUTHOR]

Nanotechnology has drawn an enormous amount of attention by providing various measures to reduce energy consumption. Phosphor-converted white-light emitting diodes (pc-w-LEDs), which are used in lighting applications, are gaining popularity. These materials are affordable, effective, and safe for the environment. Therefore, the main objective of the current study is to synthesize an economical phosphor which consumes low energy and is less harmful to the environment. In this study, Dysprosium (Dy3+) doped Potassium Strontium Vanadate (KSrVO4) nanopowders synthesized via the combustion process and using X-ray diffraction, FESEM, EDAX, HRTEM, UV-Vis spectroscopy, and photoluminescence spectroscopy techniques, we have examined its various structural, spectroscopic, optical, and morphological characteristics. The crystallite size was estimated using the XRD patterns and was found to be 25.724 nm. The functional groups contained in synthesized phosphor were identified using FTIR spectrum measurements. Using HRTEM, a particle size of 36.33 nm was predicted, which is consistent with the XRD results. The Kubelka-Munk approximation is used to determine the band gap energy of the produced nanophosphors. Three major peaks that correspond to the transitions of 4F9/2 → 6HJ (J = 15/2, 13/2, and 11/2) were discovered at 476 nm, 578 nm, and 669 nm, respectively, under the excitation of 390 nm near UV light. We investigated the impact of Dy3+ doping, the enhancement of emission intensity and the mechanism of concentration quenching on the photoluminescence spectra of the KSrVO4 host. KSrVO4:Dy3+ also demonstrated a suitable CCT (3745 K), enhanced color purity and high quantum yield in this work, indicating that this phosphor has potential applications in w-LED devices. [ABSTRACT FROM AUTHOR]

The adsorption analysis of some organic inhibitors consisting of benzotriazole, 8-hydroxyquinoline, 2-mercaptobenzothiazole onto aluminum alloy surface based on optimized coordination of binding on the Al–X (Mg, Ga, Si) surface has been accomplished. In this work, the ONIOM approach has been performed with a three-layered level of high level of DFT method using EPR-III, 6-31+G(d,p) and LANL2DZ basis sets by the physico-chemical software of Gaussian 16 revision C.01 program, a medium semi-active part that includes important electronic contributions, and a low level part that has been handled using MM2 force field approaches. The physico-chemical properties of adsorption -surface complexes are one of the principal parameters for determining and choosing the Langmuir adsorption through IR, NMR, UV–Vis, HOMO/LUMO and charge distribution results. Comparing to amounts approved a good agreement among computed results, as well as the correctness of the selected isotherm for the adsorption process of benzotriazole → Al–Mg, benzotriazole → Al–Ga, benzotriazole → Al–Si, 8-hydroxyquinoline → Al–Mg, 8-hydroxyquinoline → Al–Ga, 8-hydroxyquinoline → Al–Si, 2-mercaptobenzothiazole, 2-mercaptobenzothiazole → Al–Mg, 2-mercaptobenzothiazole → Al–Ga, and 2-mercaptobenzothiazole → Al–Si. Nuclear magnetic resonance has certainly has focused on the aluminum shielding in the intra-atomic interaction with magnesium, gallium and silicon and simultaneously interatomic interaction with other atoms in organic inhibitors through variety of high, medium and low layers of ONIOM method. Al–Si with highest fluctuation in the shielding tensors of NMR spectrum generated by intra-atomic interaction leads us to the most influence in the neighbor atoms generated by interatomic reaction. Moreover, based on the computed amounts of UV–Vis spectra for benzotriazole, 8-hydroxyquinoline and 2-mercaptobenzothiazole adsorb on the Al(111)-alloy surface, there are maximum adsorption bands between 200–280 nm for benzotriazole, 225–350 nm for 8-hydroxyquinoline and 210–280 nm for 2-mercaptobenzothiazole, respectively; and maximum adsorption bands for benzotriazole, 8-hydroxyquinoline, and 2-mercaptobenzothiazole has observed around 230, 300, and 240 nm, respectively. [ABSTRACT FROM AUTHOR]

A new layered hybrid compound, based on imidazole derivative and Zn (II), was synthesized and characterized by X-ray diffraction, infrared spectroscopy, and UV–VIS absorption spectroscopy. According to the X-ray structure, the structure was determined in the monoclinic system (C2/c space group). The packing of bis-(5-nitrobenzimidzolium) tetrachlorozincate monohydrate is characterized by an alternation of corrugated layers parallel to the (102) planes, which are composed of (C7H6N3O2)+ groups, [ZnCl4]2− anions, and water molecules. There are many H-bonds between organic molecules, inorganic groups, and water molecules. These are the main forces that hold the supramolecular structure together. Through the use of contact enrichment ratios and Hirshfeld surfaces, the intermolecular interactions of the structure were investigated. With the aid of complex impedance spectroscopy, it is possible to comprehend the electrical behavior of the synthesized substance. Molecular docking was further employed to analyze the molecular mechanism and modalities of interactions between (C7H6N3O2)2[ZnCl4]·H2O and double-stranded DNA, revealing a high degree of stability and spontaneity at the molecular level. Moreover, utilizing disk diffusion methods, the antibacterial activity of the Zn (II) complex alone and with antibiotics was studied, revealing a synergistic impact against Klebsiella pneumonia and Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

Four new coordination frameworks with formulas of {[Co(fdca)(4-bpmp)(H2O)2]·2H2O}n (1), {[Ni(fdca)(4-bpmp)(H2O)2]·2H2O}n (2), [Co(tdca)(4-bpmp)(H2O)]n (3) and [Co(fuma)(4-bpmp)(H2O)2]n (4) [4-bpmp = bis (4-pyridylmethyl)piperazine, fdca = 2,5-furandicarboxylic acid, tdca = 2,5-thiophenedicarboxylic acid, fuma = fumaric acid] have been synthesized and structurally characterized by elemental analysis, single-crystal X-ray diffraction analysis and thermogravimetric analysis. Complex 3 exhibits a 4-connected sqc6 uninodal 3D structure with point symbol of {66}, while the other three complexes all exhibit mutually inclined 2D + 2D → 3D interpenetration structures. The magnetic properties reveal that complex 1, 2, and 4 show the antiferromagnetic exchange interaction behavior. An observed difference in structure and magnetic behavior in complex 3 is driven by coordination types of carboxylate building blocks and the final structure. Magnetic study indicates the magnetic-exchange coupling not only depends on the nature of the metal centers but the structure of the metal–organic framework can affect the magnetic. And then, the UV–Vis DRS properties of four complexes were also investigated. [ABSTRACT FROM AUTHOR]

Hypochlorite is known to oxidatively degrade the corrin ring of cobalamin. Here, transient reaction intermediates are described in the reaction of aqua as well as of cyano-cobalamin with hypochlorite, using stopped-flow UV–vis kinetics. For aqua-cobalamin, the intermediate is assigned as arising from substitution of the aqua ligand with hypochlorite. For cyano-cobalamin, the intermediate is proposed to arise from substitution of the benzimidazole ligand trans to the cyanide. In both cases, the intermediates would feature a new Co(III)-OCl−bond—which is also supported by density functional theory (DFT) calculations. [ABSTRACT FROM AUTHOR]

Context: Triazene compounds (-NNN(H)-) exhibit versatility in biological, physical, and chemical applications. In their anionic form (-NNN-)(-), they can act as coordinating sites for metals, forming metallic complexes. In this study, two new isomeric triazene compounds with meta- and para-substituents in their neutral and anionic forms were investigated. A combination of detailed experimental spectroscopic characterization and computational chemistry analyses were employed. The new compounds, 1-(2-benzamide)-3-(3-nitrophenyl) triazene (m-TZN) and 1-(2-benzamide)-3-(4-nitrophenyl) triazene (p-TZN), were compared to 1,3-diphenyltriazene (dph-TZN) to understand the effects of functionalization and targeted triazene deprotonation. The anionic forms are stable, and our investigation suggests that these new compounds are suitable tridentate ligands that can act as chelating agents for metallic cations in stable complexes, similar to those found in vitamin B12. Methods: The absorption, vibrational, and electronic properties of the newly synthesized triazene compounds were extensively characterized using FT-IR/FT-Raman and UV-Vis spectroscopy. Their distinct molecular properties, intramolecular hydrogen bond effects, stability, and electronic transitions were investigated using the ORCA software. These analyses involved DFT and TD-DFT calculations at the ωB97X-D3/Def2-TZVP level of theory with THF CPCM implicit solvation to determine the molecular topology and electronic structure. The advanced STEOM-DLPNO-CCSD method for excited states was employed, enabling an in-depth analysis of ground and excited-state chemistry, accounting for precise electronic correlation and solvation effects. Explicit THF solvation was tested on the full TD-DFT ωB97X-D3/Def2-TZVP level and using ONIOM on the STEOM calculation. Reactivity was studied using Fukui functions, and action as chelating agents was investigated using GFN-xTB2 and DFT. [ABSTRACT FROM AUTHOR]

This article reports the successful synthesis of high-purity NaZr 2 PO 4 3 : Eu 3 + 0.5 mol. % - 5 mol. % phosphate phosphor by solution combustion synthesis which emits in the reddish region. The x-ray diffraction, Raman spectroscopy, x-ray photoelectron spectroscopy, photoluminescence spectroscopy, and diffuse reflectance spectroscopy measurements have all been used to analyze the synthesized phosphor's structural, vibrational, elemental composition, electronic, and optical characteristics in detail. Due to the preponderance of the magnetic dipole transition of the Eu3+ ions, the synthesized phosphors illuminated at the near ultraviolet light indicated the emission in the visible area. The phosphor's computed photometric characteristics indicated that the emission is in the reddish region with a high color purity of 94%. These findings demonstrated that the phosphor might work well in a variety of optoelectronic devices, including phosphor-converted white-light-emitting diodes. [ABSTRACT FROM AUTHOR]

In this work, we investigate the structural and optical properties of the LiNbO3 compound. The sample is prepared using the solid–solid (LN1) and sol–gel (LN2) methods. The obtained compounds were characterized by X-ray diffraction, UV–Vis and IR spectroscopy. X-ray diffraction analysis using Rietveld refinement shows that all our samples are single-phase and crystallize in the rhombohedral structure with the R 3 ¯ c space group. The UV–Vis measurements, performed from 200 to 2400 nm, show a direct and wide optical band-gap evaluated by reflectance measurements at (4.90 ± 0.02) eV and (4.24 ± 0.02) eV for LN1 and LN2, respectively. The estimation of the Urbach energy shows a lower value for LN1 which confirms the high quality of the sol–gel prepared sample. In addition, the evolution of the extinction coefficient (ke) and the refractive index n with the wavelength were determined. Furthermore, we have demonstrated that n obeys to Cauchy relation. Some other optical parameters such as the skin depth and the optical conductivity were calculated. The infrared (IR) spectra described different modes of stretching and vibration related to the functional groups that exist in the samples. The obtained encouraging results prompt us to propose this compound as a basic material for optoelectronic devices. [ABSTRACT FROM AUTHOR]

Co(II) cobalamin (Co(IICbl) is easily oxidized to Co(III) by a variety of oxidizing agents; with hydrogen peroxide, this reaction entails oxygenation of the corrin ring to species known as stable yellow corrinoids (SYC), as described by Makarov and co-workers. Reported here is a stopped-flow UV–Vis analysis of the initial steps of the Co(II)Cbl with hydrogen peroxide, prior to formation of SYC. The earliest recorded spectra in this reaction, 2 ms after mixing, consist of a mixture of Co(II) and Co(III)-aqua cobalamin. Direct formation of SYC is observed from this stage, with no evidence of inner-sphere interaction between Co(II) and the oxidant, hydrogen peroxide. Outer-sphere monoelectronic oxidation of Co(II) by H2O2 with concerted formation of a hydroxyl radical is therefore proposed as the source of subsequent SYC formation. [ABSTRACT FROM AUTHOR]

Zn-doped TiO2 (0,3,7% wt.) thin films were obtained by Sol-Gel method, deposited by spin-coating process on glass substrates, then heat treated at 500 °C for 90 min. Deposited films (Zn: TiO2) have been characterized using X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), UV–vis transmittance spectroscopy and m-lines spectroscopy (MLS). XRD analysis of the undoped TiO2 films showed the formation of both phases (anatase and brookite) with A(101) plan as preferential orientation. Increase of zinc concentration inhibited the crystal growth in the TiO2 films. SEM pictures of undoped TiO2 and Zn doped films indicate that zinc contents can lead to significant microstructure changes of TiO2 films. The average transmittance and the optical band gap of the films are 70–90% in the wavelength range 350–900 nm and 3.6–3.51 eV, respectively. M-lines spectroscopy put into evidence that Zn: TiO2 planar waveguides support single confined guided modes for both transverse electric (TE) and transverse magnetic (TM) polarizations. MLS measurements proved that doping zinc in TiO2 increased the index refraction of TiO2 thin films which enhances the waveguiding properties. Simultaneously, the birefringence decreases with increasing concentrations up to 7 wt%. Highlights: Zn doped TiO2 thin films have been synthesized by sol-gel spin-coating process. XRD, SEM, UV-Vis, and MLS characterizations of Zn-doped TiO2 thin films. Increase of zinc concentration inhibited the crystal growth in the TiO2 films. Zinc doping had a direct impact on the significant microstructure changes of TiO2 films. The obtained results demonstrate that Zn doping improves the waveguiding properties. [ABSTRACT FROM AUTHOR]

In the present study, the inorganic compound CoCl2, which is composed of two large halogen atoms, Cl, and one heavy metal atom, Co, has been added in different amounts, {0, 0.25, 0.5, 0.75, 1, and 1.5 g}, to the raw components of arsenic-borate glass containing Na+, Ca++, and Pb++ cations. X-ray diffraction patterns (XRD), Fourier transform infrared spectra (FTIR), and differential scanning calorimetry (DSC) were used to examine the glass samples that were prepared by rapid quenching of the molten in the air at room temperature. The Co-free sample as well as the Co-doped samples showed an amorphous glass' networks containing different structural units (BO3, BO4, ASO4, and PbO4). The increase in CoCl2 content caused BO3 units to convert to BO4 units and vanish the pbO4 units gradually. The values of the bulk density, Urbach's energy, linear refractive index, absorption index, linear attenuation coefficient, and optical reflectance all increased as CoCl2 content increased. While, on the other side, the values of the optical band gaps, the half-value layer, and the optical transmittance all decreased as Co-content increased. Co-rich sample may be suitable for gamma shielding purposes as well as opto-electronic devices like reflection sensors or glasses that block light. [ABSTRACT FROM AUTHOR]

Eight edible and non-edible oils have been characterized using UV–Vis absorption and transmission, FTIR, and Raman spectroscopy. Oils' molecular structure, characteristics, and type of bonds have been analyzed separately. Black seed oil and Olive oil have the maximum number of absorbance peaks in the UV–Vis range. There are absorbance peak positions in the range of 250 to 350 nm within all samples. Moreover, FTIR vibrational modes related to molecular structures have been characterized. Also, hierarchical agglomerative clustering was done using the Euclidean metric and the Ward linkage method. Cluster dendrogram trees were drawn based on the UV–Vis transmission and FTIR spectral data, which show four clusters for these eight types of oils. There are two distinct regions in the Raman spectra of edible oils. The first region is 1000–1800 cm−1 as the fingerprint region. The second one is about 2500 to 4200 cm−1. Clustering of Raman spectral data shows two main clusters: edible vegetable and non-edible oils. Also, the first cluster has two distinctive sub-clusters, including cooking oils and medical skin care oils. It shows that the Raman spectra can effectively separate the oils in this clustering method. It means that the molecular structure, transparency, colors, densities, chemical bonding, and other features of oils can be classified by this clustering method. Therefore, spectroscopic data clustering can use for more accurate oil diagnosis and oil classification. In conclusion, the hierarchical agglomerative clustering can be used effectively as a complementary method alongside UV–Vis, FTIR, and Raman spectroscopy. [ABSTRACT FROM AUTHOR]

In this paper, we designed new dyes (D-1 to D-5) with anchoring groups to test their stability for semiconductor surfaces with silyl unit as dye-sensitized solar cells (DSSCs). To investigate their photovoltaic efficiency, density functional theory (DFT) calculations were conducted with these novel D-π-D-A(Semiconductor) type structures using N,N-dimethylaniline and benzenesulfonate as electron donor (D) and a thiophene as π-conjugated spacers, with different semiconductor units as anchoring and electron acceptor units. A new dye structure as a reference (Ref-D) had been extended from methyl orange (MO) molecular structure with electron acceptor semiconducting units to improve the electronic transmission and increased maximum absorbance (λmax) to derive these new dyes (D-1 to D-5). The computed λmax of MO was obtained by testing DFT functional to benchmark it with its experimental λmax. Out of these functionals, the Coulomb-attenuating Becke, 3-parameter, Lee–Yang–Parr (CAM-B3LYP) functional having hybrid and long range correlation with 6-31G + (d,p) produced a nearly similar λmax (459 nm) as of its experimental one (464 nm). Their ionization potentials (I1) ranged between 2.65 and 5.31 eV which showed their good electron-donating nature. Their λmax values ranged between 532 and 565 nm which had a considerable red shift from Ref-D (465 nm). The highest second-order nonlinear optical (NLO) response of 134,532 Debye-Angstrom−1 was noted for dye D-2 which had the shortest bandgap. The charge tripping analysis of all the dyes miscible with the Ref-D showed an exclusive shift from highest occupied molecular orbital (HOMO) of reference to lowest unoccupied molecular orbital (LUMO) of dye. The density of states (DOS) calculations were performed with the dye D-5 to show that electronic transmission was from the dye towards the semiconductor in an efficient way. The inclusion of thiophene as π-conjugated spacer resulted in a significant increase in absorbance peak at around 80 nm. The DFT computed results offered an insight upon design of novel DSSCs with silyl anchoring groups for improved stability and efficiency. The present research is in a kind of prediction to develop new NLO materials with D-π-A design involving semiconductor as anchoring groups to attach with a DSSC surface. [ABSTRACT FROM AUTHOR]

In India's rural and urban areas, leaves, fruits, seeds, and bark of the Azadirachta indica (Neem) tree are used to treat several diseases due to their medicinal properties. Neem leaf contains bioactive elements (Ca, Na, Mg, K, and Zn) and compounds such as Quercetin which show anti-cancerous activity. In the beginning, two types of neem leaf samples have been selected; one is natural leaf powder prepared in our laboratory and the other is purchased from a well-known company. The laser-induced breakdown spectroscopy (LIBS) technique has been used to analyze the compositions responsible for showing the medicinal properties. The spectral lines of various elements like minerals (Ca, Cu, Cr, Fe, Mg, Mn, P, K, Si, Na, and Zn), heavy metals (Al, Ba, Sr, and Ti), and organic elements (C, H, N, and O) have been confirmed in the LIBS spectra of the Neem leaf samples. In addition to the spectral lines of these elements, electronic bands of CN violet band system and C2 swan band system, NH band system, NO band system, and SiO band system have also been observed in the LIBS spectra of the samples. Fourier transform Infrared (FT-IR) spectroscopy confirmed the presence of molecular bands. Ultraviolet–Visible (UV–Vis) absorption technique has been used to detect phytoconstituents, especially anti-cancerous biomolecules such as Quercetin. Further, to see the effects of soil/ground on elemental compositions, the neem leaves of different parts of India have also been taken to evaluate the elemental compositions using LIBS coupled with PCA. Leaves of another plant known as 'Mithi Neem' (Murraya Koenigii) has also collected from the same site to check its elemental compositions. The results of the present study reveal that the Neem leaves powder obtained from the commercial manufacturing company is not pure and is adulterated with a high concentration of heavy elements. Moreover, the elemental compositions of Neem and Mithi neem leaf have been discussed. [ABSTRACT FROM AUTHOR]

The present work reports the influence of Lanthanum (La) substitution on the structural, optical, electrical, and magnetic properties of bismuth ferrite (BiFeO3) nanoparticles (NPs). The compositions of Bi1−xLaxFeO3 (0% < x < 20%) NPs, with 5% Bi-excess, were synthesized through sol–gel conventional route. The XRD results suggest the formation of rhombohedral perovskite structure (R3c space group) along with a minor secondary phase. The crystallite size calculated from XRD and FESEM was observed to decrease from 60.0 to 40.0 nm with an increase in La content. The bandgap calculated using UV–Vis spectroscopy was found to decrease with La doping, and PL spectroscopy infers formation of defects in La–BFO NPs. The P–E loop studies reveal that La-doped BFO exhibits ferroelectric behavior at room temperature. The various parameters such as spontaneous polarization, dielectric constant, and distribution parameter of relaxation time measured from the electrical investigation were found to increase up to 5% La doping BFO then start decreasing with further increase in the La content in BFO. The impedance spectra of La–BFO was fitted using the theory of Cole–Cole with R(C(R(QR)))(CR) model. It is observed that La-concentration above 5% generates excess space charge which might cross the threshold to start conduction resulting in degrading of multiferroic properties. The DC magnetization study revealed the ferromagnetic behavior of the samples at room temperature. It is observed that La substitution affects the shape of the magnetization hysteresis curve beyond 5% La-concentration, and transforming it to a neck-like formation providing evidence for the spin-canting effect in the samples. These results make La-doped BiFeO3 NPs a propitious candidate for the multiferroic applications like high-density data storage devices and supercapacitors. [ABSTRACT FROM AUTHOR]

Zinc titanate (ZnTiO3) was grown on silicon and porous silicon. ZnTiO3 layers were prepared by sol-gel method. Porous silicon was fabricated by electrochemical etching of silicon in HF solution. The effect of substrate porosity on morphology, structure and otpical properties of ZnTiO3 nanostructures has been studied. Theses properties were investigated using XRD, Ultraviolet–Visible spectroscopy, and HRTEM. Some important parameters (absorption, reflectivity (R (%) and grain size) were studied. It was found that the Structural, morphology and optical properties of ZnTiO3 layers are dependent strongly on the type of substrates. The crystalline size decreased for ZnTiO3 layers deposited on PS substrate. The average grain size is about 80 nm for ZnTiO3 grown on porous silicon. The surface morphology of films was also found to be uniform and homogeneous. ZnTiO3-PS shows enhancing photon absorption compared to ZnTiO3-Si. [ABSTRACT FROM AUTHOR]

At room temperature, NixZn1-x-yCoyFe2O4 (x = 0.0 y = 0.0, x = 0.8 y = 0.0, x = 1.0 y = 0.0, x = 0.0 y = 0.8, x = 0.0 y = 1.0, x = 0.4 y = 0.4) were synthesized using the sol–gel method. Using pure nickel, zinc and cobalt ferrite as control group, and the structure and properties of ferrites containing two substituents were analyzed by each characterization. According to the X-ray diffraction (XRD) results, the prepared samples have spinel structures and no other impurity phases. Fourier transform infrared (FT-IR) spectroscopy examines the completeness and functional group information of the preparation procedure, and the samples' spinel structures were once again confirmed. Using a UV–Vis absorption spectrum examines the samples' band-gap value, and verifies their semiconductor properties. According to the scanning electron microscope (SEM), the sample agglomerates because of its magnetism, and forms a spherical cube. Besides, the narrow particle-size distribution shows a homogeneous sample size. Energy-dispersive spectroscopy (EDS) analyzes the sample which does not contain other impurity elements, and the element composition was consistent with the chemical formula of the prepared sample. A vibrating sample magnetometer (VSM) was used to examine the magnetic characteristics of the different samples. The superparamagnetism of zinc ferrite, ferromagnetism of cobalt ferrite, and sub-ferromagnetism of nickel ferrite could be obtained from the hysteresis loop diagram. [ABSTRACT FROM AUTHOR]

A chemical co-precipitation method is used to synthesize the Zn1–xCoxO nanoparticles and then examine its structural, morphological, chemical bond and magnetic properties. A single phase hexagonal wurtzite crystal structure is confirmed by X-ray diffraction for all the samples without any impurity phase. The substitution of Co-doping in ZnO lattice is confirmed by the peak shifting in XRD patterns, and reduction in crystallite size of Co-doped ZnO NPs. The enhanced optical absorption and red shift in band edge is observed in the Co-doped ZnO NPs. The reduced optical bandgap is found in Co dopant and which decreases further with increase in the Co content. M–H measurements show the ferromagnetic behavior of Co-doped ZnO NPs increases with increase in the Co content. This observed ferromagnetism is originated from increased oxygen vacancies which form bound magnetic polarons. These findings promote the usage of Co-doped ZnO materials for potential spintronics and magneto-optical applications. [ABSTRACT FROM AUTHOR]

Background: The organic dyes with non-fullerene acceptors (NFAs) have aided in the creation of competitive organic solar cells (OSCs) with long-term sustainability. A series of NFA dyes (IDIC-R1–IDIC-R9) have been designed by varying the end-capped fluorinated moieties (PD1–PD6) at indaceno (IDIC) core. Methods: All the calculations were performed by density functional theory (DFT) and time-dependent DFT (TD-DFT)–based approaches. All the geometries were optimized at B3LYP/6-31G + (d,p) of DFT level at their ground state energies. Out of several density functionals, the CAM-B3LYP with 6-31G + (d,p) basis sets was selected after a benchmark study to carry out further calculations. All the dyes had their bandgaps in 0.11–3.12 eV while their starting reference dye had a bandgap value of 2.01 eV. Results: Their ionization potential (IP) implied that these dyes have strong tendency to lose electrons. The λmax of the dyes was slightly redshifted from the IDIC (476 nm) and IDIC-R (479 nm) when changing solvent polarity from methanol to DCM and then chloroforms. The natural bond orbital (NBO) analysis showed the (S63)LP → (C61-C62)π* with highest stabilization energy. Their electron injection analysis showed that these dyes can be a good anode material against the aluminum and gold electrodes. The intramolecular charge transfer (ICT) process and stability of the dyes were investigated using frontier molecular orbital (FMO) and natural bond orbital (NBO) analysis. Conclusion: Among all dyes, IDIC-R8 has the highest linear polarizability and second-order hyperpolarizability (βtotal). All the dyes demonstrated promising non-linear optical (NLO) properties due to their low charge transfer barriers. Scientists would be able to exploit these properties to identify the best NLO materials for existing applications. [ABSTRACT FROM AUTHOR]

Zinc-Imidazole coordination polymer (ZnImCP) was simply synthesized hydrothermally at relatively low temperature (70 °C) from zinc acetate and imidazole. ZnImCP was treated by sulfide solution to produce sulfur-doped samples (S-ZnImCPs). Structures of the synthesized ZnImCP and S-ZnImCPs were characterized through FTIR, PXRD, and, Raman, SEM/EDX, N2-BET, UV–VIS DRS, and pHpzc analyses. The photocatalytic performances of pristine CP and sulfur modified CPs under visible and ultra-violet irradiations for degrading the cationic methylene blue (MB) and the anionic methyl orange (MO) were investigated considering different initial pH values 4, 7 and 10. Under visible light, the results indicate that these CPs display considerable photocatalytic degradation towards the cationic MB for the initial pH 4 and 7 where degradation increases with sulfur content. While under ultra-violet, results indicate considerable photocatalytic degradation towards both dyes for the initial pH 7 and 10 where degradation increases with sulfur content which indicates the gainful of non-metal dopping. The buffering nature of CPs and the type of radiation considering determined band-gap values effectively influence the degradation mechanisms. [ABSTRACT FROM AUTHOR]

The molecular structure of Schiff base ZIm was investigated using spectroscopic (NMR, UV–vis) techniques. Theoretical calculations of the mentioned compound have been carried out using density functional theory at the B3LYP/6-31G(d) level of theory. Geometrical parameters such as bond lengths (Å) and angles (°) obtained by DFT calculations show excellent agreement with X-ray analysis result. The Hirshfeld surface (HS) analysis shows the different percentage interactions: H/H (49.8%), H/C (28.7%), N/H (15.2%) and O/H (5.7%) interactions. The 1H and 13C NMR chemical shifts with respect to TMS were calculated using the gauge-independent atomic orbital (GIAO) method in CDCl3 and compared with the experimental data. The UV–Vis spectrum of ZIm was computed with the B3LYP and CAMB3LYP functionals and the 6-31G(d) basis set in different solvents such as CHCl3, CH3CN, MeOH and DMSO. The frontier molecular orbital's (FMO's) analysis and molecular electrostatic potential surface (MEP) were investigated using theoretical calculations. The theoretical results show good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

To protect crops and improve yield, pesticides have been widely used in agricultural production. In this case, the detection of toxic residues in agricultural products is of great significance. To achieve that, spectroscopy is a commonly used analytical method, which combines the characteristics of low detection limit, wide linear range and high accuracy. At the same time, they provide simple, low-cost, fast and on-site results. The pesticide residue detection instruments based on spectral analysis have shown advantages and broad application prospects in the instrument market. In this paper, detection methods of pesticide residues based on fluorescence spectrometry, UV–vis (ultraviolet visible) spectrometry, as well as SERS (surface-enhanced Raman scattering) spectrometry are reviewed. This paper analyses and summarizes the research progress of different types of spectrometry in the detection of pesticide residues, and points out that with the development of detection and monitoring technology, the corresponding rapid detection instrument for pesticide residues has become an indispensable tool in society. [ABSTRACT FROM AUTHOR]