Gap Values Research Articles

Pharmacoinformatics, Molecular Dynamics Simulation, and Quantum Mechanics Calculation Based Phytochemical Screening of Croton bonplandianum Against Breast Cancer by Targeting Estrogen Receptor-α (ERα)

Breast cancer progression is strongly influenced by estrogen receptor-α (ERα), a ligand-activated transcription factor that regulates hormone binding, DNA interaction, and transcriptional activation. ERα plays a key role in promoting cell proliferation in breast tissue, and its overexpression is associated with the advancement of breast cancer through estrogen-mediated signaling pathways. Targeting ERα is, therefore, a promising therapeutic strategy for breast cancer. However, there are currently no phytochemical-based drug candidates approved for effectively inhibiting breast cancer progression driven by elevated ERα expression. This study aims to identify phytochemical inhibitors from Croton bonplandianum against ERα using pharmacoinformatics approaches. Eighty-three bioactive compounds from C. bonplandianum were retrieved from the IMPPAT (Indian Medicinal Plants, Phytochemistry, and Therapeutics) database and screened through molecular docking for their binding affinity to ERα. The top candidates were further evaluated through molecular dynamics simulations, ADME analysis, toxicity assessment, and quantum mechanics-based DFT calculations. The thermodynamic properties and HOMO-LUMO energy gap values indicated that the selected compounds were both stable and active. Among them, 2,3-oxidosqualene (CID-5366020) and 5,8,11-eicosatriynoic acid, trimethylsilyl ester (CID-91696396) demonstrated the most potent inhibitory activity against ERα. These findings suggest that these compounds have significant potential as therapeutic agents for breast cancer treatment by targeting ERα.

Quality Analysis Of Seameo Recfon Website Using The Webqual Method

his study aims to analyze and measure the quality of the SEAMEO RECFON website. The method used in this research is the Webqual method, which is a method or technique for measuring website quality based on end user perceptions which is used as the main reference with indicators of usability, information quality, and service interaction and the Importance Performance Analysis method. Data collection was carried out using a questionnaire of 50 questionnaires. The results showed that the level of user satisfaction with functionality has been achieved, while the level of user satisfaction with information quality has not been achieved, and the quality-of-service interaction has not been achieved. Based on the assessment of the three measurement dimensions, the usability dimension has a value of (0.245), the service interaction dimension has a difference or gap value of - (0.39) and the information dimension has a difference or gap value of - (0.26). Based on this, it can be concluded that the actual perception of quality has not been able to meet the ideal quality desired by SEAMEO RECFON website users, especially from quality attributes related to information on the website.

Mainchain and sidechain-involving H-bonded asymmetric polyimides containing rigid amide and flexible ether linkages

Hydrogen bonds (H-bonds), usually mainchain amide H-bonds, have been well recognized to play important roles in modulating the properties of polyimides (PIs) by strengthening macromolecular interaction. While the structure-properties relationships of symmetric mainchain amide H-bonded PIs have been extensively researched, the asymmetric H-bonded PIs, particularly those containing rigid-flexible backbone structure, and sidechain-involving H-bonds, have been rarely explored. Herein, starting from designed synthesis of diamine monomers, we present two series of asymmetric PIs containing rigid amide and flexible ether linkages that form mainchain amide-amide and amide-imide H-bonds, lacking or bearing pendent trifluoromethyls (-CF3) that form sidechain-involving amide-CF3 H-bonds. The presence of these three types of H-bonds were revealed by RDF simulation and confirmed by FTIR. Mainchain H-bonded PIs (PI-Ax) show higher Tg than sidechain-involving H-bonded PIs (PI-Tx), while PI-Tx series exhibit higher optical transparency and hydrophobicity, lower dielectric constant (ε′) and better mechanical properties than PI-Ax. The general researches on the PIs’ solubility, WAXD spectra, thermal properties, fluorescence emission and optical transparency, the dihedral angles (φ), fractional free volume (FFV), theoretical gas transport properties, chain geometry optimization and HOMO-LUMO energy gap (ΔE) values have been comprehensively carried out from the aspects of both experiments and theoretical calculation.

Evaluasi Implementasi Sistem Perpustakaan Universitas Esa Unggul Kebon Jeruk Dengan Metode Fitgap Dan Risk Analysis

The existing system in the organization will always have changes following the times and newneeds that exist. So that an evaluation is needed, this research aims to find out whether the librarysystem currently implemented is suitable (Fit) or there are still gaps (Gap), which then from theseresults will be used FMEA method based on the existing Gap value, so as to provide suggestionsand evaluation results to achieve the goals of system development. The result of this study is thatthe implemented library system is considered to have a Degree of Fit of 91% (20 userrequirements), Degree of Partial 9% (2 user requirements), Degree of Gap 0% (0 userrequirements). Thus it is concluded that the current library system is still in accordance with userneeds.However, development can be carried out so that the systemcan bemore optimal inmeetinguser needs.

CALCULATION OF ELECTRONIC PROPERTIES OF LiBX3 (B = Pb AND Sn; X = Br, Cl AND I) CUBIC PHASE BY DENSITY FUNCTIONAL THEORY

Perovskite solar cells utilize perovskite as the active material to convert sunlight into electrical energy. Perovskite is a compound with a crystal structure of ABX₃, where A and B are cations, and X is an anion, usually a halide. Research continues to find perovskites with high efficiency. This efficiency is related to the electronic structure, which can be analyzed using Density Functional Theory (DFT). In this study, the electronic structure of cubic phase LiBX₃ perovskites (B = Pb and Sn; X = Br, Cl, and I) is investigated using Quantum ESPRESSO software. Various parameters such as cut-off energy, k-points, and lattice constants were modified to obtain optimal values. From the optimization results, the band gap, DOS, and PDOS values for the six perovskites were obtained. The resulting band gap energy (Eg) are LiPbBr₃ at 1,71 eV, LiPbCl₃ at 1,87 eV, LiPbI₃ at 1,43 eV, LiSnBr₃ at 0,51 eV, LiSnCl₃ at 0,65 eV, and LiSnI₃ at 0,28 eV. These results show that the band gap energy values increase with the change in atomic radius from Sn to Pb and decrease with the change in atomic radius from Cl, Br to I. The electronic structure calculations of LiBX₃ (B = Pb and Sn; X = Br, Cl, and I) show semiconductor properties that have the potential to be used as light-absorbing materials in perovskite solar cells. This study states that LiBX₃ has great potential in solar cell applications and offers a deep understanding of the relationship between crystal structure and its electronic properties.

Combining the Servqual and Kano Models to Find Out How Satisfied Customers are with Swab and PCR Services

Swabs and PCR are ways to track patients infected with COVID-19. One private swab and PCR service provider in Surabaya offers swab and PCR tests with fast results and is open 24 hours a day. This research aims to determine service quality performance, identify the causes of consumer dissatisfaction, and identify service attributes that must be maintained and improved for Swab and PCR services in Surabaya. This research uses an integration of the Servqual and Kano methods. The integration of Servqual and Kano determines the service attributes to be improved. Data was obtained from a questionnaire using the five-dimensional Servqual approach, then calculated to get a gap value and categorized using the Blauth formula. The Servqual gap and the Blauth formula's category values are combined to make action decisions. The results state that swab and PCR service providers still need to improve all factors used in this research. Three attributes fall into the weak and indifferent category, so the decision that needs to be made is to ignore them because they do not affect consumer satisfaction and are not a priority for improvement. The other twenty-one attributes fall into the weak and one-dimensional category, meaning companies must improve these attributes to satisfy consumers. Companies need to make improvements to ensure better service, including increasing the number of medical officers to reduce fatigue and queues and providing training on medical procedures and communication skills for medical officers.

Cd(II)-based fish-bone-like 1D coordination polymer: structural elucidation and computational study

{[Cd(L)2(PBT)2]}n (1) [H2L = 5-nitro-isophthalic acid; PBT = 2-pyridin-4-ylbenzothiazole], 1D Coordination Polymer (1D-CP), is characterized by single crystal X-ray diffraction. The structure of 1 contains carboxylate bridges of L2- to Cd(II), where one carboxylate chelates to Cd(II) and the other -COO bridges to two neighboring Cd(II) centers that then form eight-membered dinuclear metallacycles (Cd2C2O4). The 1D chains self-assemble via H-bonding and π⋅⋅⋅π interactions to form a supramolecular aggregate that resembles a fish-bone pattern. These interactions are further explored by Hirshfeld Surface Analysis. Density Functional Theory (DFT) computations using the crystallographic parameters of 1 predicted an energy gap, ΔE (EHOMO – ELUMO) of 3.67 eV, which is comparable to the experimental band gap obtained from a Tauc’s plot, 3.73 eV. The band gap value demonstrates the semiconducting character and may be used for device fabrication. Furthermore, molecular electrostatic potential (MEP) shows strong electrophilic reaction potential and predicts reactive sites. The PBT ligand is emissive (370 nm) while H2L is non-emissive. DMF suspensions of 1 emit at 525 nm with a long lifetime, 0.715 ns compared to the lifetime of PBT (0.05 ns). This supports that extended conjugation occurs upon formation of the 1D-CP, altering the photophysics.

Q-switched Nd: YAG Fundamental and Second Harmonic Wavelengths Impact on Preparing Nb2O5 Thin Films by a PLD Technique: A Comparative study

We aim to study and investigate the structural, optical, topographical, and morphological properties of Nb2O5 thin films deposited under vacuum Q-switched Nd: YAG pulsed laser for the first time to the best of our knowledge. The obtained results of this study can contribute in different fields of applications including the optoelectronic and biomedical fields. The fundamental (1064 nm) and the visible second harmonic (532 nm) wavelengths were utilized for this purpose. The laser energy was fixed at 657 mJ. The number of pulses and the substrate temperatures were 200 laser shots and 450 ºC, respectively. The observed X-ray diffraction patterns were assigned for T-Nb2O5 that refers to the orthorhombic and H-Nb2O5 which is related to the monoclinic phases supported by Raman spectra analyses. Nb2O5 thin film deposited by Nd: YAG fundamental wavelength (1064 nm) showed a thicker film, a higher surface roughness and, on average, a larger particles size It also provided better matching of the lattice d-spacing with the standard d-spacing obtained by JPCDs cards 00-030-0873 and 00-009-0372. The optical properties including the band gap values for both direct and indirect transitions were estimated with the lower gap was reported for the thin film prepared at the fundamental wavelength. The photoluminescence analyses supported that the transitions of both prepared films were indirect. FE-SEM clarified the surface morphology of each prepared film. The EDX analyses provided the elemental compositions and the purity of the Nb2O5 prepared films.

A Preliminary Study on Structural and Optical Properties of Heat Treated Nb2O5 Nanostructure

Annealing is a heat treatment that alters the physical and sometimes chemical properties of a material to improve their crystalline structure and other important properties. This work presents the effect of post heat treatment on optical, structural, morphological, and surface roughness of Nb2O5 thin films at different temperatures (200-700oC) which to the best of our knowledge not been extensively studied yet. A clear modification in surface morphology and other studied properties was obtained. XRD results show a significant enhancement in the film’s structural properties such as a reduction in the dislocation densities and stress. The optical properties of the treated films show a clear decrease in the transmission and energy gap values which their values were found to reduce from (4.35 to 2.9) eV with heat treatment up to 600oC and re-increase at 700oC. The surface roughness was also enhanced as a result of increasing the grain size from (9.95 – 34.7) nm Finally, SEM images of the films show an obvious change in their morphology and an increase in film uniformity as a result of heat treatment. Therefore, heat treatment could be considered as a helpful method to control film characteristics. Main result should be presented quantitatively.

Physical Properties of HfO2 Nano Structures Deposited using PLD

On Quartz substrates, high purity transparent conductive the Di-Oxide of the (HfO2) Nano and micro-structure films were successfully coated. The method of (PLD) Deposition using Pulsed Laser, and the influence of laser energy was investigated. The XRD results revealed two distinct phases, cubic and monoclinic crystal shapes. Peaks in the Fourier-transform infrared (FTIR) spectra showed that HfO2 nanofilm was forming.The findings of the optical characteristics reveal an excellent transparency of nearly 80% (89 percent). As the laser wavelength decreases, the optical energy band gap values for Nanostructure of HfO2 were prepared, with values ranging from 5.24 to 5.53 eV. Also, the EDX results showed the appearance of hafnium peaks and oxygen peaks in varying proportions, which confirms that hafnium oxide is definitely obtained The results of the AFM reveal that when the pulsed laser intensity increases, the average grain diameter values increase from 52.96 to 74.54 nm. With regard to optimum pulsed laser energy, the based on I-V characterization, the generated factor ideality for created diodes was discovered to be decreasing, and the corresponding values of the barrier height grew. The ideality factor of the diode made the optimum pulsed laser energy (1800 mJ) was greater (n=3.1).

Effect of solutions acidity on Haacke’s Figure of Merit of ZnO and ZnO:F thin films deposited by ultrasonic spray pyrolysis

Fluorine-doped zinc oxide (ZnO:F) thin films are valued for their potential as transparent conductive materials, particularly in optoelectronic applications. In this work, the deposition of highly conductive and transparent fluorine-doped ZnO thin films, deposited by chemical spray on glass substrates is reported. The effect of acetic (AcAc) in the initial fresh solution on Haacke’s Figure of Merit (Φ) of both zinc oxide (ZnO) and fluorine-doped zinc oxide (ZnO:F) thin films was studied. The substrate temperature was fixed to 450°C, and two deposition times (8 and 14 min) were tested. Accordingly, the optical and transport properties, as well as the structural and morphological characteristics of the films were measured. The results indicate that the samples are polycrystalline in all cases and exhibit a wurtzite-type structure of ZnO. The variation of AcAc in the starting solution causes a switch in preferential growth from (002) to (001). As the AcAc content increases, the surface morphology of the films reveals the formation of well-defined hexagonal grains, and the grain size increases. Conversely, the transmittance decreases as the acetic acid increases, which can attributed to carbon incorporation into the film. In addition, the band gap values of the films varied from 3.2 to 3.4 eV. Also, as the acetic acid concentration increased, a drop in the electrical resistivity of ZnO thin films on the order of 0.016 Ω⋅ cm was found for the ZnO:F films deposited with fresh solution for 14 min. This can be ascribed to a dense acetic cloud formed during the synthesis process, trapping volatile F species that incorporate into the ZnO lattice. This enhances Haacke’s Figure of Merit of ZnO:F films deposited with a fresh solution, demonstrating their potential use for application as transparent conductive films. This contrasts with other synthesis methods that require longer aging time in the precursor solution, making these findings useful for large-scale and more efficient production of transparent conductive films.

Study of Luminescence Phenomena of Tb (III) Containing Fluroquinoline for Application in Optoelectronic Devices.

This study presents a series of six vivid green Tb(III) complexes, denoted by the general formula [Tb(L)3.secondary sensitizers], where L represents 1-cyclopropyl-7-(4-ethylpiperazin-1-yl)-6-fluoro-4-oxoquinoline-3-carboxylic acid and secondary sensitizers consist of heterocyclic N-donor aromatic systems. The synthesis of these complexes were achieved through a solvent-assisted grinding method, and their characterization involved various techniques such as CHN analysis, FTIR, NMR, UV, XRD, and NIR spectroscopy. These analyses confirmed the successful synthesis of complexes with coordination between the quinoline moiety and the metal ion. Photoluminescence studies were conducted in solid and solution phases, revealing excellent luminescence properties. The bright green color emitted by the complexes upon exposure to UV rays was attributed to the hypersensitive 5D4 → 7F5 transition. J-O analysis indicated an asymmetrical coordination environment around in the complexes. Additionally, various radiative properties (Ared, Anred, η, βexp, σs) and band gap values were determined, highlighting the potential applications of these complexes in diverse optoelectronic fields. Chromaticity evaluation demonstrated high color purity in both solid and solution phases. Furthermore, the CCT value identified the solid complexes as a cool light source. Overall, the analyses supported the exceptional luminosity of synthesized complexes, positioning them as promising luminescent materials for a wide range of devices.

Elevating NIR photonic integration with tantalum-niobium pentoxide

In this study, we present a novel material platform based on tantalum-niobium pentoxide (TaNbO5) for integrated photonics applications. TaNbO5 demonstrates exceptional attributes suitable for both linear and nonlinear optics across a wide range of near-infrared wavelengths. Our analysis of the TaNbO5 unit cell revealed crucial lattice parameters and a direct band gap value of 2.268 eV. At a wavelength of 1550 nm, TaNbO5 exhibits a refractive index of 2.22, an extinction coefficient of 5.24 × 10−4, and other optical properties. We determine a 0.8 μm cut-off core width for single-mode TaNbO5 waveguides, which achieve efficiencies exceeding 99% for single-mode configurations and 98% for multimode structures. When coupled with conventional waveguides, TaNbO5 waveguides demonstrate excellent transmission characteristics. Notably, at a wavelength of 1.55 μm, the single-mode waveguide exhibits minimal excess loss. These findings highlight the significant potential of TaNbO5 waveguides for various near-infrared applications, emphasizing their versatility and promising performance.

Assessment of Thermoelectric Properties of Bi2Se3: Insights from Hybrid Functional Studies, Strain Engineering, and Machine Learning Methodology

AbstractThermoelectric properties in topological insulator Bi2Se3 are explored with multifaceted strategies, i.e., hybrid functional with strain and artificial intelligence methodology. The assessment with the experimental band gap values recognizes the limitations of conventional functional and the effectiveness of screened hybrid functionals. A thorough investigation into the impact of biaxial and uniaxial strain on thermoelectric parameters uncovers distinctive behaviors in n‐type and p‐type Bi2Se3, providing insights into optimal strain conditions for improved performance. Furthermore, the studies on the role of topologically non‐trivial surface states (TNSS) in thermoelectric properties reveal that TNSS significantly dominate electronic transport. Dual scattering time approximation elucidates the segregation of thermoelectric transport contributions from bulk and surface states, highlighting the importance of controlling the relaxation time ratio for enhanced thermoelectric performance. Additionally, the prediction of thermoelectric properties using Random Forest and Neural Networks models showcase impressive agreement with density functional theory predictions across varying temperatures, offering a powerful tool for understanding complex temperature‐dependent trends in thermoelectric properties. In summary, this interdisciplinary study presents a unique approach to advancing the understanding and optimization of thermoelectric properties in Bi2Se3. It provides a comprehensive framework for tailoring material behavior for diverse thermoelectric applications.

DFT investigation of thermodynamic, electronic, optical, and mechanical properties of XLiH3 (X= Mg, Ca, Sr, and Ba) hydrides for hydrogen storage and energy harvesting

The present study investigates the hydrogen storage capacity and physical properties of the perovskite hydrides XLiH3 (X = Mg, Ca, Sr, and Ba). The studied compounds MgLiH3, CaLiH3, SrLiH3, and BaLiH3 have lattice constants 3.76, 4.29, 4.64, and 5.04 Å, respectively. These compounds are also observed to be stable in cubic phase under atmospheric pressure and temperature conditions. They have hydrogen storage capacities 8.76 wt%, 5.99 wt%, 3.07 wt%, and 2.03 %, respectively. The SrLiH3 compound has the greatest Debye temperature (θD) of 344.41 K. The analysis of the electronic band structure and density of states reveals that perovskite hydrides have semiconducting characteristics with indirect band gap values of 2.66, 2.34, 1.94, and 1.37 eV, respectively. The materials are semiconductors and have suitable band gaps to be utilized in optical devices. Therefore, the optoelectronic properties of dielectric constants, absorption, and energy loss have been determined to predict the potential of materials for optoelectronic applications. Furthermore, the elastic constants, moduli, and anisotropy are also calculated for the observed materials. The Possion and Pugh ratios indicate these compounds exhibit ductile behaviour and significant anisotropy. Therefore, large values of hydrogen capacities, stabilities, and extraordinary physical behaviour make them important for hydrogen storage systems.

Improved photocatalytic activity triggered by UV light, as well as electrochemical sensing characteristics of MgO nanoparticles

ABSTRACT The current study’s objective was to investigate the potential applications of synthesised magnesium oxide nanoparticles (MgO NPs) as green fuel through solution combustion with leaves of tulsi (holy basil). The end product was further calcined for 3 h at 800°C to produce a well-crystalline nanomaterial. Transmission electron microscopy (TEM) examinations indicated a typical crystallite size of approximately 52 nm, determined by applying Scherer’s formula. The results from the scanning electron microscope (SEM) revealed a morphology that is clumped, puffy, and porous. The energy band gap (Eg) values for MgO NPs were determined to be 4.31 eV using DRS data, verifying the semiconductor behaviour of the NPs. Degradation experiments were conducted on two dyes, Fast Blue (FB) and Fast Orange (FO), exposed to UV light for 90 minutes. Under UV light, the photocatalytic degradation of FO (80.35%) and FB (80.5%) reached their maximum. A graphite paste electrode was used for cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and sensor investigations. The cyclic CVs of the MgO NPs-modified graphite paste electrode in 0.1 M NaOH were scanned at 10 to 50 mV/s to determine the specific capacitance values of 250.3 Fg−1. Based on the acquired EIS data, the MgO NPs used as the electrode displayed pseudocapacitive capacitor characteristics. Further, the proposed sensor was employed to determine the Pb2+ and Li+ ions in water and showed sensitivity in the order of 0.005 and 0.006 A. Therefore, MgO NPs synthesised via green solution combustion may have excellent applications as photocatalysts and electrochemical sensors.

Enhanced optical and structural traits of irradiated lead borate glasses via Ce3+ and Dy3+ ions with studying Radiation shielding performance

Lead borate glass is the best radiation shielding glass when lead is in high concentration. However, it has low transparency after radiation exposure. Radiation decreases transparency due to chemical and physical changes in the glass matrix, such as creating or healing defects in the glass network. The addition of rare earth elements like cerium and dysprosium oxides to lead borate glasses can improve their transparency and durability as radiation shielding barriers. The newly manufactured glasses’ optical absorption, structural, and radiation shielding properties were measured. The optical characteristics of the generated samples were examined to determine the effect of the cerium/dysprosium ratio on the structural alterations, specifically in the presence of bridging oxygen (BO) and non-bridging oxygen (NBO). Incorporating Ce3+ results in peaks at 195 nm for borate units, 225 nm for Ce3+, and a broadened peak at 393 nm due to overlapping peaks for Ce3+ and Ce4+ in the UV region. By adding Dy, multiple peaks are observed at 825, 902, 1095, 1275, and 1684 nm, corresponding to the transition from 6H15/2 ground state to 6F5/2, 6F7/2, 6F9/2, 6F11/2, and 6H11/2. The samples were also tested before and after exposure to gamma irradiation from a 60Co source at a dose of 75 kGy to assess their stability against radiation. The energy gap value during irradiation shows decreased non-bridging oxygen. The energy gap difference before and after irradiation for the M4 sample shows higher NBO to BO conversion, reducing radiation damage and improving structural stability. Furthermore, X-ray photoelectron spectroscopy was utilized to get insight into the coordination chemistry of the created glass samples. The half-value layer (HVL), radiation protection efficiency (RPE), neutron removal cross-section (FRNCS), mean free path (MFP), mass attenuation coefficients (MAC), and effective atomic numbers (Zef) of the glassy structure were calculated theoretically to assess its radiation shielding qualities. The linear attenuation coefficient order for the prepared samples was M1 > M2 > M3 > M4. The FRNCS values were 0.090, 0.083, 0.081, and 0.079 cm−1 for samples M1, M2, M3, and M4, respectively.

Amplifying the photovoltaic properties of tetrathiafulvalenes based materials by incorporation of small acceptors: a density functional theory approach

Currently, polycyclic aromatic compounds in organic solar cells (OSCs) have gained substantial consideration in research communities due to their promising characteristics. Herein, polycyclic aromatic hydrocarbons (PAHs) core-based chromophores (TTFD1-TTFD6) were designed by structural modifications of peripheral acceptor groups into TTFR. The density functional theory (DFT) and time dependent density functional theory (TD-DFT) calculations were carried out at B3LYP/6-311G (d, p) functional to explore insights for their structural, electronic, and photonic characteristics. The structural modulation unveiled notable electronic impact on the HOMO and LUMO levels across all derivatives, leading to decreased band gaps. All the designed compounds exhibited band gap ranging from 2.246 to 1.957 eV, along with wide absorption spectra of 897.071-492.274 nm. An elevated exciton dissociation rate was observed due to the lower binding energy values (Eb = 0.381 to 0.365 eV) calculated in the derivatives compared to the reference (Eb = 0.394 eV). Furthermore, data from the transition density matrix (TDM) and density of states (DOS) also corroborated the effective charge transfer process. Comparable results of Voc for reference and designed chromophores were obtained via HOMOdonor−LUMOPC71BM. The declining Voc order values was noted as TTFD5 > TTFD6 > TTFD4 > TTFD3 > TTFD2 > TTFD1 > TTFR. Interestingly, TTFD5 was found with the smallest energy gap and highest absorption value, resulting in better charge transference among all the derivatives. The results illustrated that the modification in indenofluorene based chromophores with end-capped small acceptors proved to be a significant approach in achieving favorable photovoltaic properties.

Synthesis and Characterization of Low-Dimensional Quaternary Sulfides of Thallium, Tl2Cu2GeS4, Tl2Ag2GeS4, and Tl2Ag2SnS4.

Three new low-dimensional quaternary sulfides, namely, Tl2Cu2GeS4(1), Tl2Ag2GeS4(2), and Tl2Ag2SnS4(3) were synthesized by solid-state reactions and characterized by single-crystal X-ray diffraction, spectroscopic, thermal, and photocatalytic studies. The compounds 1, 2, and 3, respectively, have centrosymmetric layered, noncentrosymmetric layered, and noncentrosymmetric one-dimensional structures, in which Cu+, Ge4+, and Sn4+ ions have tetrahedral coordination and Ag+ ion has linear, trigonal planar and tetrahedral coordinations. The monovalent thallium cations have TlS8 dodecahedral coordination and TlS7 and TlS6 coordination polyhedra of irregular shape. The compounds 1, 2, and 3 are semiconductors with the respective energy band gap values of 1.68, 2.02, and 1.90 eV. Compared to compounds 1 and 2, compound 3 has a higher efficiency value of 22.9% for the photodegradation of aqueous solution of methylene blue. Band structures and projected density of states of all three compounds were computed using density functional theory, and these results are in good agreement with experiments.

The electronic structure, optical, and transport properties of novel SrScCu3M4 (M = Se, Te) semiconductors

Abstract The density functional theory is used to investigate the complex relationships between the physical properties of the novel quaternary SrScCu3M4 (M = Se, Te) semiconductors. The computed negative formation energy values of these materials demonstrate their stable nature. The distribution of ELF around chalcogens and Cu atoms shows substantial localization, indicating strong covalent bonding. The phonon dispersion curves show that they possess excellent structure stability with no negative frequencies. The s/p states of Se and s/p/d of Te play minor roles, while Cu-d orbitals possess a considerable influence on the valence band region. The calculated band gaps without SOC for SrScCu3Se4 and SrScCu3Te4 are 1.29, and 0.90, respectively. The predicted energy gap values with SOC for SrScCu3Se4 and SrScCu3Te4 are 1.35, and 0.87, respectively. SrScCu3Se4 is a harder and more compressible material than SrScCu3Te4, as confirmed by its higher bulk modulus. The ε1(ω) values decrease and ultimately become negative, which suggests these materials are reflective. SrScCu3Te4 exhibits plasmon resonance at a high energy domain compared to SrScCu3Se4, resulting in a greater loss function. The current study can establish the potential efficiency of these materials in cutting-edge optoelectronic devices.