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We utilized density functional theory (DFT) to investigate the electronic structure and Raman spectrum of Azinphos-methyl (AzM) (C10H12N3O3PS2) both in isolation and in combination with gold nanoclusters (Aun, n = 2, 4, and 6). The research highlights a significant enhancement in Raman activity with increasing gold atom count from AzM-Au2 to AzM-Au4. The DFT calculations provide a comprehensive analysis of various electronic properties, including HOMO and LUMO energies, gap energy (Eg), ionization potential (IP), and electron affinity (EA), comparing these with experimental results from Liu et al. (2012). We also examined reactivity parameters, electrostatic properties, molecular electrostatic potential (MEP), Natural bond orbital (NBO) analysis, and atomsin-molecules theory (AIM). The binding energy trends among the (AzM)-Aun complexes revealed a hierarchy: (AzM)-Au2 > (AzM)-Au6 > (AzM)-Au4. Monte Carlo simulations were used to explore AzM interactions with gold nanoparticles (AuNPs) of various shapes and sizes, indicating that increased Raman intensity correlates with higher global electrophilicity and total polarizability. The results suggested that the stability of the complexes improves with more gold atoms, as evidenced by greater charge transfer, interaction energies, and second-order stabilization energies (E²). Among the complexes studied, AzM-Au2 showed the highest stability. Monte Carlo simulations revealed that the right circular cone-shaped structure, especially at 7 nm, demonstrated the most negative adsorption energy, indicating stronger adsorption interactions. This research fills a gap in previous studies on AzM, providing valuable insights and serving as a reference for future work. [ABSTRACT FROM AUTHOR]

The present work provides Potential Energy Curves (PECs) of both cyano radical CN and cyanide anion ${\rm CN}^{-}$ CN − up to the third asymptote of dissociation out of ab initio calculations. The [MRCI+Q] method is the level of theory used here and we have associated it with the Dunning basis set AV6Z (Augmented correlation-consistent polarised Valence sextet Zeta) for geometry optimisation of our systems. Electronic configurations of the states of the two species were explored and based on these configurations and the relative positions of the PECs of ${\rm CN}^{-}$ CN − against those of the neutral radical CN, stable and metastable states have been found and exhibited. The calculated electron affinity here that proves itself to be positive and the position of the ${\rm X}^{1}\Sigma ^+$ X 1 Σ + state against its corresponding neutral parent state (${\rm X}^{2}\Sigma ^+$ X 2 Σ + ) from which it derives led to confirm that this state is a long-lived and stable ground state of the cyanide anion ${\rm CN}^{-}$ CN − . Spectroscopic constants of both ground and low-lying excited states are calculated and exhibited in this work. [ABSTRACT FROM AUTHOR]

A Kesterite CZTS semiconductor contains earth-abundant elements and has been recognized as a promising absorber layer for highly efficient and low-cost thin-film solar cells. We present a numerical approach for analyzing the performance of CZTS-based photovoltaic cell with a non-toxic ZTO buffer layer through the use of a solar cell capacitance simulator. The performance of the p-CZTS/n-ZTO device has been examined in terms of ZTO buffer layer parameters such as thickness, donor concentration, mid-gap defect density, electron affinity and bandgap. The maximum cell efficiency obtained for the conduction band offset was 0.2 eV, which shows a small spike at the interface between the absorber and the buffer layers. In the optimized cell, the efficiency and fill factor were found to be 17.48% and 82.53%, respectively, which is the highest value reported so far. There are different kinds of current–voltage distortions observed, such as crossover and red-kink behavior, and the reason behind these distortions have been discussed. The results of this study provide valuable insights into the development of Cd-free highly efficient solar cells based on CZTS. [ABSTRACT FROM AUTHOR]

The holy grail of achieving efficient operation of infrared (IR) rectennas continues to be the realization of a high performance rectifier. In this paper, we have fabricated metal–insulator–metal (MIM) diodes based on TiO2, ZnO, and NiO thin films using shadow mask evaporation, photolithography, and sputtering. The electron affinities of oxides have been measured by a combination of variable angle spectroscopic ellipsometry and x-ray photoelectron spectroscopy, as well as deduction from the extraction of metal/oxide barrier heights of Fowler–Nordheim tunneling plots. Our results confirm a low value for the electron affinity of NiOx of ∼2.1–2.5 eV, which correlates with the high zero-bias dynamic resistance (RD0) of ∼500 kΩ of an associated MIM diode. These values render NiOx to be unsuitable for use in a rectenna device. Better performance has been observed from diodes based on TiO2 and ZnOx films. The best rectification performance was achieved for a Au/2.6 nm ZnOx/Cr diode, scaled down to 1 μm2 device area, showing a zero-bias dynamic resistance of RD0 = 71 kΩ, zero-bias responsivity β0 = 0.28 A/W, and a coupling efficiency of ηc = 2.4 × 10−5% for rectification at 28.3 THz. The main significance of this study is that it employs a methodology whereby key parameters of the MIM stack are derived from physical measurements, which are then used to assist in the fitting of electrical current–voltage data to produce a reliable appraisal of diode performance in an IR rectenna. [ABSTRACT FROM AUTHOR]

In recent years, Green's function methods have garnered considerable interest due to their ability to target both charged and neutral excitations. Among them, the well-established GW approximation provides accurate ionization potentials and electron affinities and can be extended to neutral excitations using the Bethe–Salpeter equation (BSE) formalism. Here, we investigate the connections between various Green's function methods and evaluate their performance for charged and neutral excitations. Comparisons with other widely known second-order wave function methods are also reported. Additionally, we calculate the singlet-triplet gap of cycl[3,3,3]azine, a model molecular emitter for thermally activated delayed fluorescence, which has the particularity of having an inverted gap thanks to a substantial contribution from the double excitations. We demonstrate that, within the GW approximation, a second-order BSE kernel with dynamical correction is required to predict this distinctive characteristic. [ABSTRACT FROM AUTHOR]

Reducing the gap between the electrodes to the nanoscale and utilizing quantum effects are an effective way to enhance the performance of a thermionic energy device. In this work, we establish the model of a photon-enhanced thermionic emission system with a nanoscale vacuum gap, where the electron transport due to electron tunneling and the near-field radiation resulting from photon tunneling are introduced. Analytical expressions for the thermionic emission current, electron tunneling current, and heat flux due to the near-field radiation are provided. By using the energy and particle balance equations, the electron concentration and the temperature of the cathode are determined. The impacts of the voltage, electron affinity, and gap distance on the performance are further analyzed. Results show that the suggested system can achieve high efficiency at the low-temperature cathode. Up to 34.7% of solar-to-electricity efficiency is possible at a cathode temperature of 472.5 K. The proposed model provides a strategy for designing highly efficient thermionic emission devices operating at low temperatures. [ABSTRACT FROM AUTHOR]

Understanding and controlling the chemical behavior of iron and iron oxide clusters requires accurate thermochemical data, which, because of the complex electronic structure of transition metal clusters, can be difficult to calculate reliably. Here, dissociation energies for Fe 2 + , Fe2O+, and Fe 2 O 2 + are measured using resonance enhanced photodissociation of clusters contained in a cryogenically cooled ion trap. The photodissociation action spectrum of each species exhibits an abrupt onset for the production of Fe+ photofragments from which bond dissociation energies are deduced for Fe 2 + (2.529 ± 0.006 eV), Fe2O+ (3.503 ± 0.006 eV), and Fe 2 O 2 + (4.104 ± 0.006 eV). Using previously measured ionization potentials and electron affinities for Fe and Fe2, bond dissociation energies are determined for Fe2 (0.93 ± 0.01 eV) and Fe 2 − (1.68 ± 0.01 eV). Measured dissociation energies are used to derive heats of formation ΔfH0( Fe 2 + ) = 1344 ± 2 kJ/mol, ΔfH0(Fe2) = 737 ± 2 kJ/mol, ΔfH0( Fe 2 − ) = 649 ± 2 kJ/mol, ΔfH0(Fe2O+) = 1094 ± 2 kJ/mol, and ΔfH0( Fe 2 O 2 + ) = 853 ± 21 kJ/mol. The Fe 2 O 2 + ions studied here are determined to have a ring structure based on drift tube ion mobility measurements prior to their confinement in the cryogenic ion trap. The photodissociation measurements significantly improve the accuracy of basic thermochemical data for these small, fundamental iron and iron oxide clusters. [ABSTRACT FROM AUTHOR]

[Display omitted] Electrochemical carbon dioxide reduction reaction (CO 2 RR) is a promising technology to establish an artificial carbon cycle. Two-dimensional conjugated metal–organic frameworks (2D c-MOFs) with high electrical conductivity have great potential as catalysts. Herein, we designed a range of 2D c-MOFs with different transition metal atoms and organic ligands, TMN x O 4-x -HDQ (TM = Cr∼Cu, Mo, Ru∼Ag, W∼Au; x = 0, 2, 4; HDQ = hexadipyrazinoquinoxaline), and systematically studied their catalytic performance using density functional theory (DFT). Calculation results indicated that all of TMN x O 4-x -HDQ structures possess good thermodynamic and electrochemical stability. Notably, among the examined 37 MOFs, 6 catalysts outperformed the Cu(2 1 1) surface in terms of catalytic activity and product selectivity. Specifically, NiN 4 -HDQ emerged as an exceptional electrocatalyst for CO production in CO 2 RR, yielding a remarkable low limiting potential (U L) of −0.04 V. CuN 4 -HDQ, NiN 2 O 2 -HDQ, and PtN 2 O 2 -HDQ also exhibited high activity for HCOOH production, with U L values of −0.27, −0.29, and −0.27 V, respectively, while MnN 4 -HDQ, and NiO 4 -HDQ mainly produced CH 4 with U L values of −0.58 and −0.24 V, respectively. Furthermore, these 6 catalysts efficiently suppressed the competitive hydrogen evolution reaction. Machine learning (ML) analysis revealed that the key intrinsic factors influencing CO 2 RR performance of these 2D c-MOFs include electron affinity (E A), electronegativity (χ), the first ionization energy (I e), p-band center of the coordinated N/O atom (ε p), the radius of metal atom (r), and d-band center (ε d). Our findings may provide valuable insights for the exploration of highly active and selective CO 2 RR electrocatalysts. [ABSTRACT FROM AUTHOR]

Fourteen substituted diketopyrrolopyrrole (DPP) molecules in a donor (D)–acceptor (DPP)–donor (D) arrangement were designed. We employed density functional theory, time‐dependent DFT, DFT‐MRCI and the ab initio wave function second‐order algebraic diagrammatic construction (ADC(2)) methods to investigate theoretically these systems. The examined aromatic substituents have one, two, or three hetero‐ and non‐hetero rings. We comprehensively investigated their optical, electronic, and charge transport properties to evaluate potential applications in organic electronic devices. We found that the donor substituents based on one, two, or three aromatic rings bonded to the DPP core can improve the efficiency of an organic solar cell by fine‐tuning the highest occupied molecular orbital/lowest unoccupied molecular orbital levels to match acceptors in typical bulk heterojunctions acceptors. Several properties of interest for organic photovoltaic devices were computed. We show that the investigated molecules are promising for applications as donor materials when combined with typical acceptors in bulk heterojunctions because they have appreciable energy conversion efficiencies resulting from their low ionization potentials and high electron affinities. This scenario allows a more effective charge separation and reduces the recombination rates. A comprehensive charge transfer analysis shows that D–A (DDP)–D systems have significant intramolecular charge transfer, further confirming their promise as candidates for donor materials in solar cells. The significant photophysical properties of DPP derivatives, including the high fluorescence emission, also allow these materials to be used in organic light‐emitting diodes. [ABSTRACT FROM AUTHOR]

We present an optimization strategy for atom‐specific spin‐polarization constants within the spin‐polarized GFN2‐xTB framework, aiming to enhance the accuracy of molecular simulations. We compare a sequential and global optimization of spin parameters for hydrogen, carbon, nitrogen, oxygen, and fluorine. Sensitivity analysis using Sobol indices guides the identification of the most influential parameters for a given reference dataset, allowing for a nuanced understanding of their impact on diverse molecular properties. In the case of the W4‐11 dataset, substantial error reduction was achieved, demonstrating the potential of the optimization. Transferability of the optimized spin‐polarization constants over different properties, however, is limited, as we demonstrate by applying the optimized parameters on a set of singlet‐triplet gaps in carbenes. Further studies on ionization potentials and electron affinities highlight some inherent limitations of current extended tight‐binding methods that can not be resolved by simple parameter optimization. We conclude that the significantly improved accuracy strongly encourages the present re‐optimization of the spin‐polarization constants, whereas the limited transferability motivates a property‐specific optimization strategy. [ABSTRACT FROM AUTHOR]

Expanded polystyrene is widely produced and used due to its properties and, recently, its ability to present π–π interactions has been described. Therefore, this work proposed to use recycled polystyrene for solid phase extraction of 12 polycyclic aromatic hydrocarbons (PAHs) in aqueous samples. Recycled polystyrene films were formed and characterised by Fourier transform infrared spectroscopy, scanning electron microscopy and affinity experiments. A moderate interaction was found, which allowed its integration in pipette tip-solid phase extraction followed by HPLC-FLD analysis. The method presents limits of detection in the range of 0.05–0.14 ng mL−1 for 12 PAHs analytes, with a precision (expressed as relative standard deviation) <10%. The methodology was applied to tap water samples, and the results were compared to those obtained using the official methodology, with no statistically significant differences. The proposed method is efficient, fast and has a low consumption of organic solvent. [ABSTRACT FROM AUTHOR]

The phenothiazine-derivative dyes have been designed using phenothiazine group (donor part), thienothiophene (spacer part), and different acid groups (electron-acceptor part). Time-dependent density functional theory (TD-DFT) and density functional theory (DFT) have been used to study the electronic and optical properties of the designed dyes (B1–B10). The dye B8 has planar conformations with a dihedral angle of 0.15° which indicates electron delocalization over the molecules. The dye B6 has a low chemical hardness value. The energy gap, ionization potential, electron affinity, and chemical hardness of the dyes have been computed, and efficiency has been analyzed. The B8 dye sensitizer has a higher dipole moment (5.324 Debye) compared to the other sensitizers, due to the presence of two cyano groups in the acceptor parts. The NLO characteristics have been determined based on the polarizability and first-order hyperpolarizability values of the designed dyes. The LHE values of dye molecules ranged from 0.75 to 0.89 eV. The dye sensitizers B6 and B8 have high efficient values compared with other designed dyes. [ABSTRACT FROM AUTHOR]

Ab initio investigation of the spectroscopic constants, bond dissociation energies of germanium monohalides, germanium dihalides and their ionic systems, viz. GeX, GeX−, GeX+, GeX2, GeX2− and GeX2+ (X = F, Cl, Br and I) have been carried out using correlation consistent triple-zeta basis sets for F and Cl and similar triple-zeta basis sets with RECPs for Ge, Br and I atoms. Geometry and frequency of all the neutral and ionic systems of germanium halides are obtained using MP2, CCSD(T) and QCISD(T) methods. The energetics are obtained at the CCSD(T)//MP2, QCISD(T)//MP2, CCSD(T) and QCISD(T) levels. Electron affinity (EA) and ionization potential (IP) of the monohalides and dihalides are reported to be consistent with the data available in literature. The bond dissociation energies (BDEs) to various dissociation asymptotes for most of the ionic systems are to be reported new in literature. The BDEs of the neutral germanium dihalides GeX2 are calculated by using the BDEs of GeX2− and GeX2+ ions and EA and IP of the associated neutral systems. A good agreement is found between the calculated values and the data wherever available. The BDEs of GeX2 for higher halogen member are reported to be new in literature. The enthalpies of formation for atomization and ionization of the neutral GeX2 dihalides are also reported here. The enthalpies of ionization are reported first time in literature and found consistent with other group IV dihalides. The reported molecular properties may be helpful to understand the chemistry involved in the plasma-assisted fabrication process of the Ge-based modern microelectronic devices, as well as will serve as a future reference. [ABSTRACT FROM AUTHOR]

As a type of cellulose ether, cyanoethyl cellulose (CEC) is considered to be a promising candidate for polymer dielectrics due to its sustainable nature and high dielectric constant induced by the cyano groups. However, the relatively high conduction loss of CEC arising from the charge motion across the polymer degrades its dielectric properties. In this work, we designed and synthesized an all‐organic polymer composite of CEC/itaconic anhydride (ITA) to improve dielectric properties. The CEC matrix was graft functionalized by ITA via an esterification reaction between the anhydride groups of ITA and hydroxyl groups of CEC. Meanwhile, crosslinking structure was also established in the composite by the generation of diester. Significantly improved dielectric constant (εr), elevated breakdown strength (Eb), restrained dielectric loss (tan δ) and decreased conductivity (σ) were observed in the composites compared with unmodified CEC. The εr increased from 17 for pure CEC to 32 for CEC/ITA at 1 kHz, and Eb also soared from 145 MV m−1 for CEC to 226 MV m−1 for the composite. The tan δ reduced from 0.24 for pure CEC to about 0.05 for the composite at 100 Hz. This should be attributed to the molecule trapping centers arising from the high electron affinity ITA and the formation of crosslinked networks as well as hydrogen bonding, which impeded the electric conduction. It also provided additional advantages of better dielectric properties for the CEC/ITA composites than pure CEC at high temperatures, which may offer inspiration for the design and preparation of bio‐based dielectrics for high temperatures. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In this work, we develop a new semiempirical method, dubbed NOTCH (Natural Orbital Tied Constructed Hamiltonian). Compared to existing semiempirical methods, NOTCH is less empirical in its functional form as well as parameterization. Specifically, in NOTCH, (1) the core electrons are treated explicitly; (2) the nuclear–nuclear repulsion term is calculated analytically, without any empirical parameterization; (3) the contraction coefficients of the atomic orbital (AO) basis depend on the coordinates of the neighboring atoms, which allows the size of AOs to depend on the molecular environment, despite the fact that a minimal basis set is used; (4) the one-center integrals of free atoms are derived from scalar relativistic multireference equation-of-motion coupled cluster calculations instead of empirical fitting, drastically reducing the number of necessary empirical parameters; (5) the (AA|AB) and (AB|AB)-type two-center integrals are explicitly included, going beyond the neglect of differential diatomic overlap approximation; and (6) the integrals depend on the atomic charges, effectively mimicking the "breathing" of AOs when the atomic charge varies. For this preliminary report, the model has been parameterized for the elements H–Ne, giving only 8 empirical global parameters. Preliminary results on the ionization potentials, electron affinities, and excitation energies of atoms and diatomic molecules, as well as the equilibrium geometries, vibrational frequencies dipole moments, and bond dissociation energies of diatomic molecules, show that the accuracy of NOTCH rivals or exceeds those of popular semiempirical methods (including PM3, PM7, OM2, OM3, GFN-xTB, and GFN2-xTB) as well as the cost-effective ab initio method Hartree–Fock-3c. [ABSTRACT FROM AUTHOR]

Machine learning (ML) has demonstrated its potential usefulness for the development of density functional theory methods. In this work, we construct an ML model to correct the density functional approximations, which adopts semilocal descriptors of electron density and density derivative and is trained by accurate reference data of relative and absolute energies. The resulting ML-corrected functional is tested on a comprehensive dataset including various types of energetic properties. Particularly, the ML-corrected Becke's three parameters and the Lee–Yang–Parr correlation (B3LYP) functional achieves a substantial improvement over the original B3LYP on the prediction of total energies of atoms and molecules and atomization energies, and a marginal improvement on the prediction of ionization potentials, electron affinities, and bond dissociation energies; whereas, it preserves the same level of accuracy for isomerization energies and reaction barrier heights. The ML-corrected functional allows for fully self-consistent-field calculation with similar efficiency to the parent functional. This study highlights the progress of building an ML correction toward achieving a functional that performs uniformly better than B3LYP. [ABSTRACT FROM AUTHOR]

Opto-electrical properties of MgxZn1−xO can be tuned by adjusting the value of x, but phase separation occurs when x is greater than 0.4. Hydrogen acts as a shallow donor in MgxZn1−xO and can play an important role in tuning the opto-electrical properties in a way that avoids phase separation. Mg0.1Zn0.9O (MZO) films were prepared at different hydrogen partial pressures and their structures and properties were studied. XRD results show that the MZO film has a wurtzite structure with a preferential orientation along the c-axis, but the crystallinity declines with increasing hydrogen partial pressure. Stress in the MZO film changes from tensile to compressive as the hydrogen partial pressure increases. Increasing the hydrogen partial pressure improves the conductivity and increases the optical bandgap, but the electronic affinity of MZO decreases, according to ultraviolet photoelectron spectroscopy results. These key parameters were used to simulate a device with a TCO/MZO/CdTe/ZnTe:Cu type structure, in which TCO is the transparent conductive oxide. The highest efficiency of 17.37% was achieved when the electron affinity of the MZO film was 3.71 eV, corresponding to a spark-like band offset of 0.29 eV at the MZO/CdTe interface. These results suggest that the electron affinity of MZO can be tuned to achieve an optimal band alignment in the device. [ABSTRACT FROM AUTHOR]

A cost‐effective chemical prelithiation solution, which consists of Li+, polyaromatic hydrocarbon (PAH), and solvent, is developed for a model hard carbon (HC) electrode. Naphthalene and methyl‐substituted naphthalene PAHs, namely 2‐methylnaphthalene and 1‐methylnaphthalene, are first compared. Grafting an electron‐donating methyl group onto the benzene ring can decrease electron affinity and thus reduce the redox potential, which is validated by density functional theory calculations. Ethylene glycol dimethyl ether (G1), diethylene glycol dimethyl ether, and triethylene glycol dimethyl ether solvents are then compared. The G1 solution has the highest conductivity and least steric hindrance, and thus the 1‐methylnaphthalene/G1 solution shows superior prelithiation capability. In addition, the effects of the interaction time between Li+ and 1‐methylnaphthalene in G1 solvent on the electrochemical properties of a prelithiated HC electrode are investigated. Nuclear magnetic resonance data confirm that 10‐h aging is needed to achieve a stable solution coordination state and thus optimal prelithiation efficacy. It is also found that appropriate prelithiation creates a more Li+‐conducing and robust solid‐electrolyte interphase, improving the rate capability and cycling stability of the HC electrode. [ABSTRACT FROM AUTHOR]

Transmission-mode (t-mode) GaAs negative electron affinity photocathodes (NEA-PCs) can be integrated with the optical focusing lenses and microchannel plates to produce high-quality electron beams and high-sensitive detectors. Quantum efficiency (QE) of ∼40% has been reported for the t-mode thick (>1000 nm) GaAs NEA-PCs. Nevertheless, practical applications of these devices have been seriously restricted by their long response time (tens of picoseconds). In this work, the all-dielectric meta-surfaces (ADMS) were designed as the light managers for the t-mode ultra-thin GaAs NEA-PCs. For the 500–850 nm waveband, high light absorption (>80%) can be obtained through coupling the electromagnetic dipole moments of ADMS into the leaky optical modes in 100 nm ultra-thin GaAs NEA-PC layer, which leads to enhanced QE higher than that of the thick ones, the response time less than 5 ps, and the mean transverse energy less than 60 meV, respectively. Given these properties, ADMS t-model ultra-thin NEA-PCs represent a promising photocathode to provide the high-brightness short-pulse spin-polarized electron beams and high-sensitive fast-response detectors for the electron accelerator and low-light-level photodetection applications, respectively. [ABSTRACT FROM AUTHOR]

An optical waveguide that transmits the electromagnetic waves is a critical component for various optoelectrical applications including integrated optical circuits and optical communications. Among many, the 1D tubular optical waveguide structure enables efficient distant energy transfer via mode selection within the optical microcavity. However, its application is limited due to the complicated fabrication process. Herein, hexagonal tris(8‐hydroxyquinoline) aluminum (Alq3) microtubes with an average longitudinal length of ≈15 µm are self‐assembled within few minutes by utilizing 1‐butyl‐3‐methylimidazolium tetrafluoroborate (BMIMBF4) ionic liquids. The swift fabrication is enabled by the high electron affinity of BMIMBF4 that forms hexagonal microrods. Also, BMIMBF4 ionic liquid etches the central region of micorods during its growth, forming microtubes with a wall thickness of ≈650 nm. The fabricated Alq3 microtubes show significantly improved waveguide characteristics with reduced optical loss coefficient (0.054 µm−1) compared to that of microrods (0.271 µm−1). The demonstrated method to fabricate Alq3 microtubes with ionic liquid is an efficient approach to utilize organic microstructures as an optoelectrical components for advanced optical communications. [ABSTRACT FROM AUTHOR]

The current study explores the potential of MgO-supported finite-sized TiMg n (n = 2–6) nanoclusters as hydrogen storage materials, employing density functional theory with a spin-polarized generalized gradient approximation (GGA). These systems' structural stability and electronic characteristics reveal that supported clusters offer superior hydrogen storage capabilities compared to their unassisted counterparts. Various parameters, including cluster-adsorption energy (E ads), hydrogen-adsorption energy in supported clusters (E ads -H), HOMO-LUMO gap, vertical ionization potential (VIP), vertical electron affinity (VEA), chemical potential (μ), and chemical hardness (ɳ) are computed. Substrate support notably enhances the thermodynamic stability and chemical reactivity of the TiMg 5 cluster when contrasted with the bare TiMg 5 cluster. Furthermore, a remarkable increase in the gravimetric hydrogen storage density, from 1.63 wt% for bare Mg 5 clusters to 3.45 wt% for bare TiMg 5 clusters, reaching 5.62 wt% in the supported TiMg 5 cluster system is observed. These findings indicate the substrate-supported TiMg 5 cluster as a promising candidate for hydrogen storage applications. [Display omitted] • Utilized DFT to investigate hydrogen storage capabilities of Mg n and TiMg n (n = 2–6) clusters supported on MgO. • Upon hydrogenation, Mg 5 and TiMg 5 clusters exhibited heightened chemical hardness, enhancing their resistance to reactions. • H 2 storage efficiency was credited to the plenty of reactive sites on the cluster's surface and the system's stability. • Achieved hydrogen gravimetric density of 5.62 wt% in supported TiMg 5 clusters through hydrogen adsorption. • Among different TiMg n clusters, supported TiMg 5 demonstrated superior efficiency in both hydrogen storage and dissociation. [ABSTRACT FROM AUTHOR]

Numerous synthetic routes have been established for the synthesis of organotin (IV) derivatives of carboxylates, thiocarbamates, thiols, alcohols, amines, Schiff bases, etc. However, no synthetic path has been still developed for the synthesis of organotin (IV) aldehydes. We have synthesized four O,S‐coordinated organotin (IV) aldehydes (1–4) of the general formulas LSn(S)(Cl)R2 (where R2 = Me2, n‐Bu2, Ph2 for 1–3, respectively) and LSn(S)Ph3 (4) by reaction of 4‐(dimethylamino)benzaldehyde (L) with KOH, CS2, and R2SnCl2/Ph3SnCl in methanol. The synthesized products were characterized by microanalysis (CHN), FT‐IR analysis, UV–visible spectroscopy, NMR spectroscopy (1H and 13C), thermogravimetric analysis (TGA), computational studies, and single‐crystal XRD. Elemental analysis data were agreed well with the molecular composition of the products. FT‐IR spectroscopy has shown a significant lowering of C=O vibrational frequency after ligand–metal coordination. The electronic spectroscopy of complexes 1–4 demonstrated the π–π* (342–343 nm) and n–π* (279–296 nm) transitions, with the band gap values of 3.15–3.38 eV. 1H NMR spectra displayed distinct signals for the ligand skeleton and organotin (IV) moieties. 13C NMR spectroscopy exhibited an upfield shift of carbonyl oxygen after ligand–metal coordination. The thermogravimetric analysis revealed the thermal stabilities of complexes up to a temperature of 190 to 320°C. Single‐crystal XRD analysis of product 4 has shown a distorted trigonal bipyramidal geometry around Sn (IV), in which the three phenyl groups were positioned equatorially while the carbonyl oxygen (from the aldehyde) and the sulfur atom occupied the apical positions. Employing the 6‐31G(d,p) basis set and the CAM‐B3LYP functional, time‐dependent density functional theory (TD‐DFT) computations were performed for the calculation of absorbance maxima, oscillator strength (f), and matching molecular designations. MEP maps and HOMO–LUMO energy gaps were predicated on the CAM‐B3LYP/6‐31+g(d,p) level of theory and were used to resolve GRD, including chemical potential (μ), global hardness (η), global softness (S), electronegativity (χ), electrophilicity (ω), ionization potential (IP), and electron affinity (EA). The phenyltin (IV) derivatives (3 and 4) have shown a fantastic biofilm inhibition of Escherichia coli, which was even higher as compared with that of the reference drug ciprofloxacin. The bioactivity of 2 against Bacillus subtilis was equivalent to that of the ciprofloxacin. The products 2 and 3 have shown very little (less than 10%) toxic hemolytic effects demonstrating their possible safe use for the human beings. [ABSTRACT FROM AUTHOR]

Carbon‐based allotropes are propelling a technological revolution in communication, sensing, and computing, concurrently challenging fundamental theories of the previous century. Nevertheless, the demand for advanced carbon‐based materials remains substantial. The crux lies in the efficient and reliable engineering of novel carbon allotrope. Although C18 has undergone theoretical and experimental investigation for an extended period, its preparation and direct observation in the condensed phase occurred only recently through STM/AFM techniques. The distinctive cyclic ring structure and the dual 18‐center π delocalization character introduce various uncommon properties to C18, rendering it a subject worthy of in‐depth exploration. In this context, this review delves into past developments contributing to the state‐of‐the‐art understanding of C18 and provides insights into how future endeavours can expedite practical applications. Encompassing a broad spectrum, this review comprehensively investigates almost all facets of C18, including geometric characteristics, electron delocalization, bonding nature, aromaticity, reactivity, electronic excitation, UV/Vis spectrum, intermolecular interaction, response to external fields, electron affinity, ionization, and other molecular properties. Moreover, the review also outlines representative strategies for the direct synthesis and characterization of C18 using atom manipulation techniques. Following this, C18‐based complexes are summarized, and potential applications in catalysis, electrochemical devices, optoelectronics, and sensing are discussed. [ABSTRACT FROM AUTHOR]

The immune biological response systems and inflammation can be triggered by a number of things such as pathogens, damaged cells and toxic substances. In ethnomedicine, leaves of Lemon basil (Ocimum basilicum citriodorum) have been used for their health benefits. This study examines the anti-inflammatory properties of lemon basil stalks. In a GC/MS study, 24 plant-based bioactive compounds were identified. Comparing the activities in 24 compounds with the largest negative binding energy values helped us determine which compound was most active. It can be seen that only two compounds (Campstool and stigmasterol) with the highest binding energies interact with the 2QVD protein; consequently, the compound with the highest binding energy has superior anti-inflammatory activity. In quantum mechanics, electron energy difference between lowest-unoccupied molecular orbitals (LUMO) and highest-occupied molecular orbitals (HOMO) is described by the quantum-mechanical method, electronegativity (χ), electron affinity (A), global hardness (η), global softness (σ) and ionization potential (I) estimated from the optimized structure. Higher energy molecules are more reactive than other substances reported in this study. [ABSTRACT FROM AUTHOR]

Monolayer and few-layer CoPS3 have been successfully synthesized via an Au-assisted exfoliation technique, with their transport properties subsequently investigated by conductive atomic force microscopy. Rectification effects can be observed in CoPS3 nanosheets due to the Schottky junction formation at the Au/CoPS3 interface, especially in configurations comprising two or more layer flakes. The distinct transport properties between monolayer and few-layer samples demonstrate that the charge transport behavior in the vertical direction is associated with the van der Waals gap. The calculated electron affinity for CoPS3 is about 4.84 eV, as revealed by the thermionic emission model. The results obtained contribute to the knowledge base concerning the transport characteristics of ultrathin MPX3, facilitating further exploration of the transport behavior of these materials and their potential applications in novel electronic devices. [ABSTRACT FROM AUTHOR]

Superacids are systems that exhibit higher acidity compared to extremely strong mineral acid, i.e. 100% pure sulphuric acid (H2SO4). They can be designed by the protonation of appropriate superhalogen anions. Superhalogens possess higher electron affinity (EA) than halogens. Most recent examples include CF 4 − n ( SO 3) n , which behave as superhalogens for n = 1 − 4. In this work, we studied the protonation of CF 4 − n ( SO 3) n − using density functional theory calculations at the B3LYP/6-311 + + G (d , p) level. The Gibbs' free energies of deprotonation (Δ G acid ) values of the resulting protonated complexes, HCF 4 − n ( SO 3) n for n = 1 –4; are either lower or nearly equivalent to that of H2SO4 (Δ G acid = 3 0 2. 2 kcal/mol). This suggests that all these protonated complexes exhibit superacidic behavior. Notably, the HC ( SO 3) 4 compound undergoes significant structural relaxation, leading to a remarkably less Δ G acid value. Our findings should enrich the literature with a new series of superacids and motivate further studies to explore novel organic superacids. [ABSTRACT FROM AUTHOR]

Electrostatic capacitors, with the advantages of high-power density, fast charging–discharging, and outstanding cyclic stability, have become important energy storage devices for modern power electronics. However, the insulation performance of the dielectrics in capacitors will significantly deteriorate under the conditions of high temperatures and electric fields, resulting in limited capacitive performance. In this paper, we report a method to improve the high-temperature energy storage performance of a polymer dielectric for capacitors by incorporating an extremely low loading of 0.5 wt% carbon quantum dots (CQDs) into a fluorene polyester (FPE) polymer. CQDs possess a high electron affinity energy, enabling them to capture migrating carriers and exhibit a unique Coulomb-blocking effect to scatter electrons, thereby restricting electron migration. As a result, the breakdown strength and energy storage properties of the CQD/FPE nanocomposites are significantly enhanced. For instance, the energy density of 0.5 wt% CQD/FPE nanocomposites at room temperature, with an efficiency (η) exceeding 90%, reached 9.6 J/cm3. At the discharge energy density of 0.5 wt%, the CQD/FPE nanocomposites remained at 4.53 J/cm3 with an efficiency (η) exceeding 90% at 150 °C, which surpasses lots of reported results. [ABSTRACT FROM AUTHOR]

Spin-polarized photoemission from wurtzite and zinc blende gallium nitride (GaN) photocathodes has been observed and measured. The p-doped GaN photocathodes were epitaxially grown and activated to negative electron affinity with a cesium monolayer deposited on their surfaces. A field-retarding Mott polarimeter was used to measure the spin polarization of electrons photoemitted from the top of the valence band. A spectral scan with a tunable optical parametric amplifier constructed to provide low-bandwidth light revealed peak spin polarizations of 17% and 29% in the wurtzite and zinc blende photocathodes, respectively. Zinc blende GaN results are analyzed with a spin polarization model accounting for experimental parameters used in the measurements, while possible mechanisms influencing the obtained spin polarization values of wurtzite GaN are discussed. [ABSTRACT FROM AUTHOR]

Multimodal haptic perception is essential for enhancing perceptual experiences in augmented reality applications. To date, several artificial tactile interfaces have been developed to perceive pressure and precontact signals, while simultaneously detecting object type and softness with quantified modulus still remains challenging. Here, inspired by the campaniform sensilla on insect antennae, we proposed a hemispherical bimodal intelligent tactile sensor (BITS) array using the triboelectric effect. The system is capable of softness identification, modulus quantification, and material type recognition. In principle, due to the varied deformability of materials, the BITS generates unique triboelectric output fingerprints when in contact with the tested object. Furthermore, owing to the different electron affinities, the BITS array can accurately recognize material type (99.4% accuracy), facilitating softness recognition (100% accuracy) and modulus quantification. It is promising that the BITS based on the triboelectric effect has the potential to be miniaturized to provide real-time accurate haptic information as an artificial antenna toward applications of human-machine integration. [ABSTRACT FROM AUTHOR]

This study explores the variation of highly symmetric points in the band structure, revealing a shift from G-X symmetric K path to Z-G path under the influence of mechanical stress. Notably, the band gap decreased linearly with increasing mechanical stress, while the effective mass of the electron, heavy hole, and light hole exhibited different trends. The variation of band gap, effective mass of electron, heavy and light holes, electron affinity, dielectric constant in x and y direction has been found to be -0.1238 eV/GPa, -6E-3 1/GPa, -7.9E-3 1/GPa, 1.4E-2 1/GPa, 4.7e-2 eV/GPa, 7.3e-2 1/GPa and -10.3e-2 1/GPa, respectively. [ABSTRACT FROM AUTHOR]

The key motive of the current work is the detailed study of charge transport and optoelectronic properties of Benzotrifuran based organic molecules for organic electronic device applications. Density functional theory (DFT) and time dependent‐DFT simulations were executed on studied organic molecules. The absorption characteristics are ascertained and the results are compared with corresponding known experimental results. Frontier molecular orbitals, that is; highest occupied molecular orbital and lowest unoccupied molecular orbital, electron extraction potential, electron affinities, ionization potentials, reorganization energies (Z), and hole extraction potential of all the studied molecules are explored. In contrast, all of the examined organic compounds are with low hole (Zh) and electron (Ze) reorganization energies, making them suitable for use in organic electrical devices. [ABSTRACT FROM AUTHOR]

For the first time, the oxidative polymerizations of o/m-anisidines and o-toluidine were carried out by ammonium peroxydisulfate in organic medium. According to the results of UV–Vis, 1H NMR and IR spectral methods the structures of the synthesized poly(o-anisidine) coincide with emeraldine base. Formation of dihydrobenzoxazole units was shown for poly(m-anisidine), which lowers the amount of both quinonediimine and methoxy groups in polymer. Obtained polymers show enhanced solubility in organic solvents. Thermal analysis shows that at 800 °C polyanisidines lost only 48% of their initial weight. Room temperature conductivity measurements show correspondingly 2.5 × 10−1 S/cm and 9 × 10−3 S/cm values for poly(o-anisidine) and poly(o-toluidine) when doped with inorganic acids. The ionization potential and electron affinities of obtained polymers were estimated by cyclic voltammograms. [ABSTRACT FROM AUTHOR]

The primary goals of this project are to analyze the structure and assess the photovoltaic performance of n-i-p structured formamidinium tin iodide (FASnI3) perovskite solar cells at different operating temperatures to inspect the impact of operating temperature on device performance using a Solar Cell Capacitance Simulator (SCAPS). The simulated device structure is Au/spiro-OMeTAD/P3HT/FASnI3/PCBM/TiO2/FTO, whereas spiro-OMeTAD and TiO2 serve as the hole transport layer and electron transport layer, respectively. SCAPS simulation has been performed at 200, 300, 400, 500, and 600 K operating temperatures, and corresponding current density vs voltage (J–V) characteristics have been studied in addition to the photovoltaic metrics, such as open circuit voltage (VOC), short circuit current density (JSC), fill factor (FF), and power conversion efficiency (PCE). The thickness fluctuation and doping concentration variation of the absorber layer and the electron affinity variation and thickness variation of the Hole Transport Layer (HTL) and Electron Transport Layer (ETL) under temperature variation were also examined analytically. It has been found that there is an inverse relationship between temperature and power conversion efficiency (PCE). The extended thickness of the absorber layer enhances the PCE and JSC. Temperature variations in the thickness of the ETL and HTL have a minimal effect on the PCE and JSC of the device. At standard room temperature (300 K operating temperature), the solar cell parameters are found to be a short-circuit current density (JSC) of 17.93 mA/cm2, open-circuit voltage (VOC) of 1.06 V, fill factor (FF) of 67.46% and power conversion efficiency (PCE) of 17.93%. [ABSTRACT FROM AUTHOR]

[Display omitted] Carbonyl or imine-based compounds have received a great deal of attention due to their high specific capacity and designability as cathodes for aqueous rechargeable organo-aluminum batteries. However, the inherent low conductivity and high solubility of carbonyl and imine-based compounds severely affect the cycling stability of aluminum batteries. Therefore, it is urgent to find an organic cathodes material with low solubility and good cycling performance. In this work, dibenzo[ a , c ]dibenzo[5,6:7,8]quinoxalino[2,3-i]phenazine-10,21-dione (DDQP) were synthesized by simple dehydration condensation to form new imine covalent bonds, which led to the synthesis of imine-conjugated backbone structures with carbonyl, extended π-conjugation planes, and increased active sites, resulting in increased specific capacities. Its storage mechanism with Al(OTF) 2 + has also been confirmed. This monovalent ion usually possesses a lower coulombic interaction, which leads to a reduced solubility of DDQP during redox processes and improves its cyclic stability. The specific capacity of DDQP is 252.22 mAh/g at a current density of 400 mA g−1. After cycling, the discharge specific capacity remains at 219 mAh/g. Surprisingly, the conductivity of the battery also is improved by this structure of multiple active sites. And it can be further confirmed by theoretical calculations that the synthesis of DDQP realigns the arrangement of the electron cloud, enhances the electron affinity, and reduces the energy gap. This study provides a new reference for improving the performance of aqueous organic aluminum batteries. [ABSTRACT FROM AUTHOR]

Superalkalis (SAs) are exotic clusters having lower ionization energy than alkali atoms, which makes them strong reducing agents. In the quest for the reduction of diatomic molecules (X2) such as N2, O2, and H2 using Møller‐Plesset perturbation theory (MP2), we have studied their interaction with typical superalkalis such as FLi2, OLi3, and NLi4 and calculated various parameters of the resulting SA−X2 complexes. We noticed that the SA−O2 complex and its isomers possess strong ionic interaction, which leads to the reduction of O2 to O2− anion. On the contrary, there are both ionic and covalent interactions in SA−N2 complexes such that the lowest energy isomers are covalently bonded with no charge transfer from SA. Further, the interaction between SA and H2 leads to weakly bound complexes, which results in the adsorption of H2 molecules. The nature of interaction is found to be closely related to the electron affinity of diatomic molecules. These findings might be useful in the study of the activation, reduction, and adsorption of small molecules, which can be further explored for their possible applications. [ABSTRACT FROM AUTHOR]

The influence of polar solvents, such as water (H2O), on the physical properties of the paracetamol molecule was investigated using the Density Function Theory (DFT) approach. Using a polar solvent (water), the values of ionization potential (IP) and electron affinity (EA) rise, while (LUMO) and total energy depress, indicating the highly reactive molecule in electrophile processes. Paracetamol has no detrimental impacts on human health, according to the conclusions of a study on the consequences of dissolving paracetamol in water, and is consequently used to treat headaches. The Characteristics such as (UV-VIS), (FT-IR), and (NMR) spectra were utilized to describe the paracetamol molecule and establish the structural optimization utilizing the B3LYP/3-21G basis set. Based on the IR and UV-visible spectra, the water solvent has a lower impact on this band compared with the results for pure paracetamol. Using (UV-VIS) spectra, the paracetamol molecule's (π → π*) transition shifts to a shorter wavelength after being dissolved in water, which is dependent on the formation of an inter-hydrogen bond. After studying the dissolution of paracetamol in water as a polar solvent, the zero-point energy and nuclear repulsion energy values were discovered, that attitude to the interaction of the polar solvent with the drug's energy levels. Furthermore, the dipole moment with using water increases because the polar solvent stabilizes the excitation state more than the ground state, this is called a dipole-dipole interaction. The addition of water leads to an increase the enthalpy and vibration energy, which may be too high to interact with electronic levels for drugs and water. [ABSTRACT FROM AUTHOR]

Low‐bandgap nonfullerene acceptors (NFAs) offer a unique potential for photovoltaic (PV) applications, such as transparent PV and agrivoltaics. Evaluating each new PV system to achieve the optimum thickness, microstructure, and device performance is, however, a complex multiparametric challenge with large time and resource requirements. Herein, the PV potential of low‐bandgap donor and NFA materials by combining high‐throughput screening and statistical methods is evaluated. The use of thickness gradients (20–600 nm) facilitates the fabrication of more than 2000 doctor‐bladed devices from 24 different low‐bandgap blend combinations. The corresponding power conversion efficiencies varies significantly, from 0.06% to 10.45% across materials and thicknesses. The self‐consistency of the large dataset allows to perform a parameter sensitivity study as well as parameter correlation analysis. These reveal that the choice of materials and energy alignment‐related features (i.e., electron affinity offset, ionization energy offset, bandgap, and energy loss) has the largest influence on final device performance, while processing conditions appear less important for the final efficiencies. Our study demonstrates that high‐throughput experimentation is a perfect match for correlation analyses in order to gain a statistically meaningful understanding of these systems, potentially accelerating the discovery of new materials. [ABSTRACT FROM AUTHOR]

A cooperative strategy for simultaneously improving typically conflict properties between mechanical strength and self-healability of elastomers is developed by combining the strong electron-withdrawing and high free-volume effects of fluorine atoms, resulting in the highest recorded puncture energy (648.0 mJ) elastomer so far. [Display omitted] There is usually a trade-off between high mechanical strength and dynamic self-healing because the mechanisms of these properties are mutually exclusive. Herein, we design and fabricate a fluorinated phenolic polyurethane (FPPU) elastomer based on octafluoro-4,4′-biphenol to overcome this challenge. This fluorine-based motif not only tunes interchain interactions through π−π stacking between aromatic rings and free-volume among polymer chains but also improves the reversibility of phenol-carbamate bonds via electron-withdrawing effect of fluorine atoms. The developed FPPU elastomer shows the highest recorded puncture energy (648.0 mJ), high tensile strength (27.0 MPa), as well as excellent self-healing efficiency (92.3%), along with low surface energy (50.9 MJ m−2), notch-insensitivity, and reprocessability compared with non-fluorinated counterpart biphenolic polyurethane (BPPU) elastomer. Taking advantage of the above-mentioned merits of FPPU elastomer, we prepare an anti-fouling triboelectric nanogenerator (TENG) with a self-healable, and reprocessable elastic substrate. Benefiting from stronger electron affinity of fluorine atoms than hydrogen atoms, this electronic device exhibits ultrahigh peak open-circuit voltage of 302.3 V compared to the TENG fabricated from BPPU elastomer. Furthermore, a healable and stretchable conductive composite is prepared. This research provides a distinct and general pathway toward constructing high-performance elastomers and will enable a series of new applications. [ABSTRACT FROM AUTHOR]

A method integrating machine learning with first-principles calculations is employed to forecast the formation energy of delafossite crystals, facilitating the rapid identification of stable crystals. This approach identifies several stable candidates and highlights the importance of atomic ionization energy and electron affinity in the formation of delafossite crystals. [ABSTRACT FROM AUTHOR]

Phenolic acids still gain significant attention due to their potential antimicrobial and cytotoxic properties. In this study, we have investigated the antimicrobial of six phenolic acids, namely chlorogenic, caffeic, p-coumaric, rosmarinic, gallic and tannic acids in the concentration range 0.5–500 μM, against Escherichia coli and Lactobacillus rhamnosus. The antimicrobial activity was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide colorimetric assay. Additionally, the cytotoxic effects of these phenolic acids on two cancer cell lines, the colorectal adenocarcinoma Caco-2 cell line and Dukes' type C colorectal adenocarcinoma DLD-1 cell line was examined. To further understand the molecular properties of these phenolic acids, quantum chemical calculations were performed using the Gaussian 09W program. Parameters such as ionization potential, electron affinity, electronegativity, chemical hardness, chemical softness, dipole moment, and electrophilicity index were obtained. The lipophilicity properties represented by logP parameter was also discussed. This study provides a comprehensive evaluation of the antimicrobial and cytotoxic activity of six phenolic acids, compounds deliberately selected due to their chemical structure. They are derivatives of benzoic or cinnamic acids with the increasing number of hydroxyl groups in the aromatic ring. The integration of experimental and computational methodologies provides a knowledge of the molecular characteristics of bioactive compounds and partial explanation of the relationship between the molecular structure and biological properties. This knowledge aids in guiding the development of bioactive components for use in dietary supplements, functional foods and pharmaceutical drugs. [ABSTRACT FROM AUTHOR]

The genome—the source of life and platform of evolution—is continuously exposed to harmful factors, both extra- and intra-cellular. Their activity causes different types of DNA damage, with approximately 80 different types of lesions having been identified so far. In this paper, the influence of a clustered DNA damage site containing imidazolone (Iz) or oxazolone (Oz) and 7,8-dihydro-8-oxo-2′-deoxyguanosine (OXOdG) on the charge transfer through the double helix as well as their electronic properties were investigated. To this end, the structures of oligo-Iz, d[A1Iz2A3OXOG4A5]*d[T5C4T3C2T1], and oligo-Oz, d[A1Oz2A3OXOG4A5]*d[T5C4T3C2T1], were optimized at the M06-2X/6-D95**//M06-2X/sto-3G level of theory in the aqueous phase using the ONIOM methodology; all the discussed energies were obtained at the M06-2X/6-31++G** level of theory. The non-equilibrated and equilibrated solvent–solute interactions were taken into consideration. The following results were found: (A) In all the discussed cases, OXOdG showed a higher predisposition to radical cation formation, and B) the excess electron migration toward Iz and Oz was preferred. However, in the case of oligo-Oz, the electron transfer from Oz2 to complementary C4 was noted during vertical to adiabatic anion relaxation, while for oligo-Iz, it was settled exclusively on the Iz2 moiety. The above was reflected in the charge transfer rate constant, vertical/adiabatic ionization potential, and electron affinity energy values, as well as the charge and spin distribution. It can be postulated that imidazolone moiety formation within the CDL ds-oligo structure and its conversion to oxazolone can significantly influence the charge migration process, depending on the C2 carbon hybridization sp2 or sp3. The above can confuse the single DNA damage recognition and removal processes, cause an increase in mutagenesis, and harm the effectiveness of anticancer therapy. [ABSTRACT FROM AUTHOR]

[Display omitted] The instability and high electron-hole recombination have limited the application of black phosphorus (BP) as an excellent photocatalyst. To address these challenges, poly dimethyl diallyl ammonium chloride (PDDA), poly (allylamine hydrochloride) (PAH), and polyethyleneimine (PEI) are introduced to the functionalization of BP (F-BP), which can not only enhance its stability, but also boost the carrier transfer. Furthermore, a high-performance heterojunction photocatalyst is fabricated using F-BP and titania nanosheets (TNs) via a layer-by-layer self-assembly approach. The experimental outcomes unequivocally indicate that F-BP exhibits fast charge migration compared to BP. The density functional theory (DFT), in situ Kelvin-probe force microscopy (KPFM) and other advanced characterization techniques collectively unfold that PDDA modified BP can notably boost separation and propagation of charges, along with an enhanced carrier abundance. In summary, this novel strategy of using polyelectrolytes to enhance the electron transfer and the stability of BP permits immense potential in building next-generation BP-based high efficiency photocatalysts. [ABSTRACT FROM AUTHOR]

Carbazole-based self-assembled monolayers have received considerable attention as hole-selective layers (HSLs) in inverted perovskite solar cells. As an HSL, the electron-blocking capability is important and directly related to electron affinity (EA). Low-energy inverse photoelectron spectroscopy (LEIPS) is the most reliable method for EA measurement. However, the intense electron-impact-induced fluorescence from carbazole interferes with their measurement. By improving the photon detector, we were able to measure 2PACz and MeO-2PACz LEIPS spectra and determine their respective EAs of 1.72 and 1.48 eV. These small EA values ensure effective electron-blocking capability of HSLs regardless of the type of perovskite layer. [ABSTRACT FROM AUTHOR]

Narrow bandgap n-InAs and several other semiconductors possess negative electron affinity. This causes serious problems while assessing free charge carrier concentration by electrical methods. Particularly, in conventional capacitance–voltage (C–V) measurements, we registered the overestimated (by several degrees) apparent carrier concentration as a result of the near-surface layer enrichment with electrons. This issue is thoroughly discussed and analyzed in this paper. Three approaches for adequate processing of C–V measurements to eliminate the considered influence of the electron-enriched surface on measured capacitance were elaborated for correct and reliable estimation of free charge carrier concentration. A novel technique combining electrochemical capacitance–voltage measurements in nonequilibrium conditions is presented. The experiment is accompanied by the numerical solution of the Poisson equation using the modified Thomas–Fermi approximation. [ABSTRACT FROM AUTHOR]

The purpose of this work is to study the characteristics of the junction between the titanium down conductor of a thin-film solid-state lithium-ion battery (a-Si) and a negative Si@O@Al nanocomposite electrode. The results of measuring the band gap of the Si@O@Al nanocomposite and the height of the Schottky barrier of the Ti–Si@O@Al junction are presented. The transmission and reflection spectra of Si@O@Al films and its main phases a-Si, a-SiOx, and a-Si(Alx) are studied. The band gap of Si@O@Al was determined by the Tauc method, which is 1.52 eV for a-Si and 1.15 eV for nc-Si. The IV characteristics of Ti‒Si@O@Al, Ti–a-Si, Ti–a-SiO0.8, and Ti–a-Si0.9(Al0.1) structures have been studied and the height of the Schottky barrier has been determined. The results obtained make it possible to estimate the Fermi energy of the nanocomposite and to interpret the hike in the SSLIB charging voltage as a result of the Al acceptor impurity compensation during lithiation. A change in the majority charge carriers in Si@O@Al leads to a decrease in the hole current and an increase in the density of the over-barrier electron current, as a result of which a step with a height of 1.5 V is formed on the charging curve. [ABSTRACT FROM AUTHOR]

This work establishes the dependences of the biological activity of synthesized dithio- and dithioseleno-containing spatially hindered phenols with α-methylbenzyl groups on the calculated values of the energy parameters of the molecules. For the studied compounds, the values of the electrophilicity index are calculated based on the obtained values of the ionization potentials and electron affinity. Using methods of multiple regression analysis, the dependences of the bactericidal and antifungal properties of the samples on two parameters were established: x1—the energy of the HOMO (highest occupied molecular orbital), and x2—the energy of the LUMO (lowest unoccupied molecular orbital) with a reliability of more than 93%. According to the equations derived based on the antimicrobial properties of bis[n-α-methylbenzyl-m-methyl-2-hydroxyphenyl] disulfides (selenides), three-dimensional graphs of functions were constructed, considering the boundary conditions of the zone of microorganism suppression around the hole on a scale of 0–3 cm. The obtained models show that changes in the energies of the LUMO (x2) have a greater effect on the zone of microorganism suppression than changes in the energies of the HOMO (x1), as indicated by the comparison of the coefficients' values for x2 and x1, respectively. Moreover, the degree of influence of changes in the energies of the boundary molecular orbitals on f antifungal properties is more significant than on bactericidal properties, based on the values of the coefficients of the equations for a mixture of fungi and bacteria at values x1 and x2. [ABSTRACT FROM AUTHOR]

Quantifying electron trapping and transfer to small molecules is crucial for interfacial chemistry. In an astrochemical context, we study how NH3 clusters in both crystalline and amorphous forms can capture low-energy electrons to form ammoniated electrons. Electron affinities, vertical detachment energies, and vertical attachment energies were computed via ab initio static and dynamics simulations, (DFT, DLPNO-CCSD(T);AIMD), for (NH3) n clusters (n = 4, 5, 6, 8, 14, 23, and 38). Our results indicate that the clusters could trap and stabilize the unpaired electron which is always externally localized on the clusters. Interactions of the ammoniated electron clusters with astrochemically relevant molecules indicate that electron transfer to water and methanol are feasible, forming the radical anions (H2O)−· and (CH3OH)−·. The trapping of electrons by both crystalline and amorphous NH3 ices, and subsequent transfer to small molecules, highlights 'astro-electrochemical' reactions, and has implications for both astrochemistry as well as terrestrial cluster science. [ABSTRACT FROM AUTHOR]

The selection of photoactive layer materials for organic solar cells (OSCs) is essential for the photoelectric conversion process. It is well known that chlorophyll is an abundant pigment in nature and is extremely valuable for photosynthesis. However, there is little research on how to improve the efficiency of chlorophyll-based OSCs by matching chlorophyll derivatives with excellent non-fullerene acceptors to form heterojunctions. Therefore in this study we utilize a chlorophyll derivative, Ce6Me3, as a donor material and investigate the performance of its heterojunction with acceptor materials. Through density functional theory, the photoelectric performances of acceptors, including the fullerene derivative PC71BM and the terminal halogenated non-fullerene DTBCIC series, are compared in detail. It is found that DTBCIC-Cl has better planarity, light absorption, electron affinity, charge reorganization energy and charge mobility than others. Ce6Me3 has good energy level matching and absorption spectral complementarity with the investigated acceptor molecules and also shows good electron donor properties. Furthermore, the designed Ce6Me3/DTBCIC interfaces have improved charge separation and reorganization rates (K CS/ K CR) compared with the Ce6Me3/PC71BM interface. This research provides a theoretical basis for the design of photoactive layer materials for chlorophyll-based OSCs. [ABSTRACT FROM AUTHOR]

The genome is continuously exposed to a variety of harmful factors that result in a significant amount of DNA damage. This article examines the influence of a multi-damage site containing oxidized imino-allantoin (OXIa) and 7,8-dihydro-8-oxo-2′-deoxyguanosine (OXOdG) on the spatial geometry, electronic properties, and ds-DNA charge transfer. The ground stage of a d[A1OXIa2A3OXOG4A5]*d[T5C4T3C2T1] structure was obtained at the M06-2X/6-D95**//M06-2X/sto-3G level of theory in the condensed phase, with the energies obtained at the M06-2X/6-31++G** level. The non-equilibrated and equilibrated solvent-solute interactions were also considered. Theoretical studies reveal that the radical cation prefers to settle on the OXOG moiety, irrespective of the presence of OXIa in a ds-oligo. The lowest vertical and adiabatic ionization potential values were found for the OXOG:::C base pair (5.94 and 5.52 [eV], respectively). Conversely, the highest vertical and adiabatic electron affinity was assigned for OXIaC as follows: 3.15 and 3.49 [eV]. The charge transfers were analyzed according to Marcus' theory. The highest value of charge transfer rate constant for hole and excess electron migration was found for the process towards the OXOGC moiety. Surprisingly, the values obtained for the driving force and activation energy of electro-transfer towards OXIa2C4 located this process in the Marcus inverted region, which is thermodynamically unfavorable. Therefore, the presence of OXIa can slow down the recognition and removal processes of other DNA lesions. However, with regard to anticancer therapy (radio/chemo), the presence of OXIa in the structure of clustered DNA damage can result in improved cancer treatment outcomes. [ABSTRACT FROM AUTHOR]