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In this paper, we investigate the Feshbach resonances of high partial waves and the influence of spin–spin (S–S) interaction on ultracold scattering processes. Taking the N a 23 - R b 87 system as an example, we plot the variations of weakly bound state energy and elastic scattering cross section with magnetic field and with collision energy. We find that the number of splittings in high partial wave Feshbach resonances does not strictly conform to the expected l + 1 (l is rotational angular momentum), and the deviation is attributed to the influence of bound states in other channels coupled by S–S interaction. For different ml (the projection of l on the external magnetic field direction), the effects of S–S interaction lead to different scattering patterns in the incident channels. These results reveal the complex features of ultracold scattering processes in high partial waves caused by S–S interaction. [ABSTRACT FROM AUTHOR]

Experimental rate coefficients for the quenching of vibrational levels 0 and 1 of the N 2 + A 2 Π u state by N2 are presented. The experiments were performed using near-infrared observations of the N 2 + Meinel bands excited by electron impact at several pressures of the N2 target/quenching gas. The total removal rate coefficients were derived from a Stern–Volmer analysis of the Meinel band intensities as a function of N2 density and yielded rate coefficients of (2.5 ± 0.5 × 10−10) and (5.6 ± 0.6 × 10−10) cm3⋅molecule−1⋅s−1 for vibrational levels 0 and 1, respectively. It is shown that rate coefficients increase with increasing vibrational level and decreasing energy gap. Our results impact modeling studies of the disturbed atmosphere and ionosphere as the reduced quenching rate coefficients for the preferentially excited A-state vibrational levels <2 lower the quenching altitude in the atmosphere by one scale height, or about 6 km. [ABSTRACT FROM AUTHOR]

Polyyne bridges have attracted extensive interest as molecular wires due to their shallow distance dependence during charge transfer. Here, we investigate whether triplet energy transfer from cadmium selenide (CdSe) quantum dots (QDs) to anthracene acceptors benefits from the high conductance associated with polyyne bridges, especially from the potential cumulene character in their excited states. Introducing π-electron rich oligoyne bridges between the surface-bound anthracene-based transmitter ligands, we explore the triplet energy transfer rate between the CdSe QDs and anthracene core. Our femtosecond transient absorption results reveal that a rate constant damping coefficient of β is 0.118 ± 0.011 Å−1, attributed to a through-bond coupling mechanism facilitated by conjugation among the anthracene core, the oligoyne bridges, and the COO⊖ anchoring group. In addition, oligoyne bridges lower the T1 energy level of the anthracene-based transmitters, enabling efficient triplet energy transfer from trapped excitons in CdSe QDs. Density-functional theory calculations suggest a slight cumulene character in these oligoyne bridges during triplet energy transfer, with diminished bond length alternation. This work demonstrates the potential of oligoyne bridges in mediating long-distance energy transfer. [ABSTRACT FROM AUTHOR]

The pure rotational and rovibrational spectra of the ν27 –NH2 torsion of cyclopropylamine (CPA) in the far-infrared region were measured with a high-resolution Fourier transform infrared coupled to a synchrotron. The complex spectra reflect the presence of both trans and gauche conformers. Analysis of the pure rotational spectra (34–64 cm−1) yielded accurate rotational and centrifugal distortion constants of the ground and first two torsional excited states of trans-CPA. The fundamental, hot bands and weak overtones were identified and assigned in the 200–550 cm−1 range. Global analysis of over 19 000 transitions provides accurate energy levels of the torsional polyads up to vT = 3. The torsional levels and their rotational constants were in agreement with the theoretical results from quasiadiabatic channel reaction path Hamiltonian (RPH) calculations, emphasizing the need for molecular-specific theoretical treatments for large amplitude motions. Tunneling components of the torsional fundamental of gauche-CPA were assigned based on the RPH results and symmetry considerations, differing from previous experimental and theoretical work. This comprehensive spectroscopic characterization of CPA is crucial for its potential detection in the interstellar medium as a precursor to complex prebiotic molecules, providing essential data for future astronomical searches and advancing our understanding of nitrogen-containing organic molecules in space. [ABSTRACT FROM AUTHOR]

Band-tail states, i.e., charge-carrier energy states located in the bandgap at the valence and conduction band edges of amorphous materials, even though not delocalized, exhibit nonzero mobility; thus, they are expected to contribute to the charge-conduction process. A microscopic model based on hydrodynamic transport equations for unipolar conduction, including trap, band-tail, and band states, and coupled to the Poisson equation is presented here. The equations are self-consistently solved by means of a numerical procedure, and the results provide qualitative and quantitative estimates of the influence of band-tail states (namely, of their energy distribution, density, and mobility) on the carrier heating, precursor of the Ovonic threshold switch. [ABSTRACT FROM AUTHOR]

Vibrational relaxation of HOD(v12, v3) molecules by collisions with Ar was studied at 298 K (v12 denotes coupled bending, v2, and OD stretching, v1, vibrational modes and v3 denotes OH stretching mode). The vibrationally excited HOD molecules were generated by exothermic abstraction reactions of OD radicals with 13 different RH reactants and observed by infrared emission from a fast-flow reactor as a function of Ar pressure and reaction time. State-specific relaxation rate constants were obtained by comparison of the time evolution of the experimental vibrational distributions with numerical kinetic calculations for vibrational populations. The relaxation mechanism was based on the relaxation scheme of H2O studied earlier with the addition of specific channels for HOD(v12, v3). Unlike H2O, energy in stretching and bending vibrations of HOD cannot be separated due to close ν1 and 2ν2 energies, which leads to fast collisional equilibration between these Fermi-resonant levels. For relaxation of the only pure bending state (10), a rate constant of (1.5 ± 0.3) × 10−13 cm3 molecule−1 s−1 was obtained. The relaxation rate of higher v12 states linearly increases with quantum number and very likely includes transfer of population from OD stretch levels, v1, to a lower energy bend level. The average rate constants for the loss of population from (01), (02), and (03) stretching states are (1.1 ± 0.3) × 10−14, (3.2 ± 1.0) × 10−14, and (5.6 ± 1.2) × 10−14 cm3 molecule−1 s−1, respectively. [ABSTRACT FROM AUTHOR]

α-Al2O3 is renowned for its extensive bandgap and diverse applications in electronic and optoelectronic devices. Employing density-functional theory-based methods, this study investigates the feasibility of chalcogen doping (S, Se, Te) in α-Al2O3. Standard modeling tools are utilized to construct α-Al2O3 supercells, focusing on the calculations of individual chalcogen-related and native point defects resulting from single-atom doping. Our analysis systematically explores the formation energies and transition levels associated with chalcogen (S, Se, Te) doping in oxygen (or aluminum) sites in Al-rich (or O-rich) limits. We observe a trend where increasing atomic number (from S to Te) correlates with a higher difficulty in forming anion-doped α-Al2O3, but a lower barrier to cationic doping. The results indicate a preferential substitution of chalcogen atoms for aluminum in O-rich environments. Specifically, in varying oxygen conditions, the dominant defect types, their prevalence, and defect formation energies in α-Al2O3 are significantly altered following chalcogen doping, offering new insights into defect processes in α-Al2O3. [ABSTRACT FROM AUTHOR]

α-Al2O3 is renowned for its extensive bandgap and diverse applications in electronic and optoelectronic devices. Employing density-functional theory-based methods, this study investigates the feasibility of chalcogen doping (S, Se, Te) in α-Al2O3. Standard modeling tools are utilized to construct α-Al2O3 supercells, focusing on the calculations of individual chalcogen-related and native point defects resulting from single-atom doping. Our analysis systematically explores the formation energies and transition levels associated with chalcogen (S, Se, Te) doping in oxygen (or aluminum) sites in Al-rich (or O-rich) limits. We observe a trend where increasing atomic number (from S to Te) correlates with a higher difficulty in forming anion-doped α-Al2O3, but a lower barrier to cationic doping. The results indicate a preferential substitution of chalcogen atoms for aluminum in O-rich environments. Specifically, in varying oxygen conditions, the dominant defect types, their prevalence, and defect formation energies in α-Al2O3 are significantly altered following chalcogen doping, offering new insights into defect processes in α-Al2O3. [ABSTRACT FROM AUTHOR]

The behavior of polyatomic molecules around their equilibrium positions can be regarded as that of quantum-coupled anharmonic oscillators. Solving the corresponding Schrödinger equations enables the interpretation or prediction of the experimental spectra of molecules. In this study, we developed a novel approach for solving the excited states of anharmonic vibrational systems. The normal coordinates of the molecules are transformed into new coordinates through a normalizing flow parameterized by a neural network. This facilitates the construction of a set of orthogonal many-body variational wavefunctions. This methodology has been validated on an exactly solvable 64-dimensional coupled harmonic oscillator, yielding numerical results with a relative error of 10−6. The neural canonical transformations are also applied to calculate the energy levels of two specific molecules, acetonitrile (CH3CN) and ethylene oxide (C2H4O). These molecules involve 12 and 15 vibrational modes, respectively. A key advantage of this approach is its flexibility concerning the potential energy surface, as it requires no specific form. Furthermore, this method can be readily implemented on large-scale distributed computing platforms, making it easy to extend to investigating complex vibrational structures. [ABSTRACT FROM AUTHOR]

Pristine and dysprosium-doped ZnO thin films, highly c-axis oriented, were grown on a c-Al2O3 substrate using the pulsed laser deposition technique. During the deposition process, the growth was impacted by changes in the oxygen partial pressure. The structural, optical, and compositional properties of the pristine and dysprosium-doped ZnO thin films were systematically characterized using various state-of-the-art experimental techniques. The crystallinity associated with these films was observed to be highly dependent on the oxygen partial pressure maintained during the growth process. An average optical transparency of more than ∼90% in the visible spectral range (i.e., 400–800 nm) was observed for all specimens. For doped specimens, expected intra-4fn emissions of (dysprosium) Dy3+ ions that emanated from the 4F9/2 energy state were observed in room-temperature photoluminescence spectra under direct excitation. The Jacobian-transformed wavelength-to-energy plot for Dy-doped ZnO thin films in the UV-Visible region revealed intriguing findings. Specifically, it depicted a prominent peak at 2.82 eV, indicative of the energy state of Dy3+ ions, alongside intense band-edge emission and various defect-related emissions. The intensity of these transitions was observed to depend on the oxygen partial pressure kept during deposition. An x-ray photoelectron spectroscopy analysis of the doped specimen confirmed the +3 oxidation state of dysprosium into the ZnO matrix. These results provide a promising approach for controlling the doping and growth strategy of Dy-doped ZnO thin films, thereby opening up a wide range of applications and enhancement for next-generation optoelectronic devices. [ABSTRACT FROM AUTHOR]

Recently, the cold source field-effect transistor (CSFET) has emerged as a promising solution to overcome Boltzmann tyranny in its ballistic regime, offering a steep-slope subthreshold swing (SS) of less than 60 mV/decade. However, challenges arise due to scattering, particularly from inelastic scattering, which can lead to significant degradation in SS through cold carrier thermalization. In this study, we delve into the theoretical investigation of the electronic excitation/relaxation dynamic process using the state-of-the-art nonadiabatic molecular dynamics (NAMD) method. The mixed quantum-classical NAMD proves to be a powerful tool for comprehensively analyzing cold carrier thermalization and transfer processes in semiconductor Si, as well as metallic silicides (NiSi 2 and CoSi 2). The approach of mixed quantum-classical NAMD takes into account both carrier decoherence and detailed balance, enabling the calculation of thermalization factors, relaxation times, scattering times, and scattering rates at various energy levels. The thermalization of carriers exhibits a gradual increase from low to high energy levels. Achieving partial thermalization from the ground state to reach the thermionic current window occurs within a sub-100 fs time scale. Full thermalization across the entire energy spectrum depends sensitively on the barrier height, with the scattering rate exponentially decreasing as the energy of the out-scattering state increases. Notably, the scattering rate of NiSi 2 and CoSi 2 is two orders of magnitude higher than that of Si, attributed to their higher density of states compared to Si. This study not only provides insights into material design for low-power tunnel field-effect transistors but also contributes valuable information for advancing CSFET in emerging technologies. [ABSTRACT FROM AUTHOR]

Single atom alloys (SAAs) often bring new chemistry in heterogeneous catalysis and well-defined structure for the study of structure–activity relationship (SAR). However, the existing pressure gap causes the reported SARs quite divergent. Herein, we have studied CO activation over Ni/Cu(100) SAAs in ultrahigh vacuum (UHV) and millibar range. While the Ni SAAs formed on Cu(100) significantly enhance the CO adsorption strength under UHV conditions, the CO treatment at elevated pressure leads to notable surface carbon and oxygen deposition through surface reaction. Density functional theory calculations revealed that either dissociation or disproportionation is thermodynamically forbidden for the coverage of CO less than 5/16 ML. However, these two reaction pathways can be opened at higher CO coverages due to the elevated energy state involving repulsion between adsorbed CO. This work uncovers the initial activation process of CO and demonstrates one typical cause for the pressure gap in surface science study as well. [ABSTRACT FROM AUTHOR]

In the continuity of a previous jet-cooled rovibrational study of trans and cis conformers of 2-furfural in the mid-infrared region (700–1750 cm−1) [Chawananon et al., Molecules 28 (10), 4165 (2023)], the present work investigates the far-infrared spectroscopy of 2-furfural using a long path absorption cell coupled to a high-resolution Fourier transform spectrometer and synchrotron radiation at the AILES beamline of the SOLEIL synchrotron. Guided by anharmonic calculations, vibrational energy levels and excited-state rotational constants are sufficiently predictive for a complete assignment of all fundamental and combination bands up to 700 cm−1, as well as the rovibrational analysis of 4 (1) low-frequency modes of trans-(cis-)2-furfural. A global rovibrational simulation, including far-infrared rovibrational lines and microwave and millimeter-wave rotational lines assigned in a previous study [Motiyenko et al., J. Mol. Spectrosc., 244, 9 (2007)] provides a reliable set of ground- and excited-state rotational parameters involving ring torsion, bending, and ring puckering modes of 2-furfural. In a second step, a rovibrational analysis of several hot band sequences, mainly involving the lowest frequency ring CHO torsion mode, is carried out. Reliable values of some anharmonic coefficients are obtained experimentally and could serve as a benchmark for validating advanced anharmonic calculations related to these large amplitude motions of flexible molecules. [ABSTRACT FROM AUTHOR]

Excited atomic nitrogen atoms play an important role in plasma formation in hypersonic shock-waves, as happens during spacecraft reentry and other high velocity vehicle applications. In this study, we have thoroughly studied collision induced excitation associated with two colliding nitrogen atoms in the N(4S), N(2D), and N(2P) states at collision energies up to 6 eV, using time-independent scattering calculations to determine cross sections and temperature-dependent rate coefficients. The calculations are based on potential curves and couplings determined in earlier multireference configuration interaction calculations with large basis sets, and the results are in good agreement with experiments where comparisons are possible. To properly consider the spin–orbit coupling matrix, we have developed a scaling method for treating transitions between different fine-structure components that only require calculations with two coupled states, and with this, we define accurate degeneracy factors for determining cross sections and rate coefficients that include all states. The results indicate that both spin–orbit and derivative coupling effects can play important roles in collisional excitation and quenching, and that although derivative coupling is always much stronger than spin–orbit, there are many transitions where only spin–orbit can contribute. As part of this, we identify two distinct pathways associated with N(2P) relaxation and one Auger-like mechanism leading to two N(2D) that could be important at high temperatures. [ABSTRACT FROM AUTHOR]

The spectrum of localized hole states (traps) in amorphous silicon nitride, a-Si3N4, is experimentally studied using the method of thermally stimulated depolarization. The experiment is compared with theoretical calculations using three models of the energy spectrum of traps: discrete spectrum (monoenergetic trap), continuous spectrum, and Gaussian trap distribution. The experiment is quantitatively described by a model of a discrete spectrum of traps with an energy of 1.15 eV and a width of no more than 0.01 eV. In the case of a continuous and Gaussian spectrum of traps, the contribution to depolarization is made by the deepest traps. The blurring of the trap energy level in a-Si3N4 due to the absence of long-range order (fluctuations in the Si–N bond length and fluctuations in the N–Si–N and Si–N–Si angles) does not exceed 0.01 eV. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to examine the impact of a before-school physical activity program on middle school students' social and emotional learning (SEL) and their energy levels. Method: A total of 171 students (67 in program group; 104 in control group) participated in the study from fall 2019 to spring 2022. The physical education teacher implemented the program 3 days per week, for 8 weeks. The students completed a 17-item SEL assessment before and after the program. The program group also reported their energy levels using an energy meter at each session. Results: Students' SEL in program group improved by 14% (p <.001) at the end of the program. Students also reported higher energy levels (p <.001) following their participation at each session. Discussion/Conclusion: Schools are encouraged to incorporate before-school physical activity programs to energize the students at the start of the school day and improve their SEL. [ABSTRACT FROM AUTHOR]

We present the results of a new analysis of the literature data on electron mobility μ in dense helium gas aimed at determining the existence of a threshold density for electron self-trapping in gaseous helium as a function of temperature. We have investigated the density dependence of μ and, when available, its dependence on the electric field. The experimental data are favorably rationalized by minimizing the excess free energy of the self-localized states within the optimum fluctuation model. It is shown that the formation of electron bubbles via the self-trapping phenomenon is determined by the delicate balance between the electron thermal energy, the density dependence of the electron energy at the bottom of the conduction band in the gas, and the work necessary to expand the bubble. We show that the self-trapping phenomenon is not limited to low temperatures but occurs at any temperatures for large enough densities. [ABSTRACT FROM AUTHOR]

A comprehensive study on the photo-excited relaxation dynamics in semiconducting perovskite quantum dots (PQDs) is pivotal in realizing their extensive potential for optoelectronics applications. Among different competing photoinduced relaxation kinetics, energy transfer and charge transfer (CT) in PQDs need special attention, as they often influence the device efficacy, particularly with the donor–acceptor hybrid architecture. In this work, we explore a detailed investigation into photoinduced CT dynamics in mixed halide undoped CsPb(Br/Cl)3 and Mn2+ doped CsPb(Br/Cl)3 PQDs with a quinone molecule, p-benzoquinone (BQ). The energy level alignment of undoped PQDs with BQ allows an efficient CT, whereas Mn2+ doping reduces the CT efficiency, experiencing a competition between energy transfer from host to dopant and CT to BQ. The conductive atomic force microscopy measurements unveil a direct correlation with the spectroscopic studies by showing a significant improvement in the conductance of undoped PQDs in the presence of BQ, while an inappreciable change is observed for doped PQDs. A much-reduced transition voltage and barrier height in the presence of BQ further validate faster CT for undoped PQD than the doped one. Furthermore, Mn2+ doping in PQDs is observed to enhance their stability, showing better air and thermal stability compared to their undoped counterparts. These results reveal that doping strategy can regulate the CT dynamics in these PQDs and increase their stability, which will be beneficial for the development of desired optoelectronic devices with long-term stability. [ABSTRACT FROM AUTHOR]

Aluminum powder particle size (D50) is quite important for how to improve the energy release level and formulation design of aluminized explosives. In this paper, four experimental samples of CL-20-based aluminized explosives with aluminum powder particle sizes including 2, 13, 24, and 43 μm were designed. The experiments were carried out through an underwater explosion tank and compared with explosives containing lithium fluoride of the same particle size. The results show that the burning of aluminum powder promoted the shock wave propagation and bubble expansion. Aluminized explosives have a lower and then higher decay rate than lithium fluoride-containing explosives. For the experimental range of aluminum powder particle sizes, with an increase in D50, the peak shock wave pressure first increased and then decreased, reaching the maximum at 24 μm; the shock wave and loss energy gradually increased, while the bubble energy, energy utilization, and underwater explosion total energy all gradually decreased. To a certain degree, the energy output structure can be regulated by adjusting the D50 under the premise of constant total energy of explosives. The experimental results improve our understanding of how D50 affects the underwater explosion parameters of aluminized explosives, which is of great significance for improving their energy utilization. [ABSTRACT FROM AUTHOR]

In the present work, the electronic structure and chemical bonding of the MoC X3Σ− ground state and the six lowest excited states, A3Δ, a1Γ, b5Σ−, c1Δ, d1Σ+, and e5Π, have been investigated in detail using multireference configuration interaction methods and basis sets, including relativistic effective core potentials. In addition, scalar relativistic effects have been considered in the second order Douglas–Kroll–Hess approximation, while spin–orbit coupling has also been calculated. Five of the investigated states, X3Σ−, A3Δ, a1Γ, c1Δ, and d1Σ+, present quadruple σ2σ2π2π2 bonds. Experimentally, the predissociation threshold of MoC was measured using resonant two-photon ionization spectroscopy, allowing for a precise measurement of the dissociation energy of the ground state. Theoretically, the complete basis set limit of the calculated dissociation energy with respect to the atomic ground state products, including corrections for scalar relativistic effects, De(D0), is computed as 5.13(5.06) eV, in excellent agreement with our measured value of D0(MoC) of 5.136(5) eV. Furthermore, the calculated dissociation energies of the states having quadruple bonds with respect to their adiabatic atomic products range from 6.22 to 7.23 eV. The excited electronic states A3Δ2 and c1Δ2 are calculated to lie at 3899 and 8057 cm−1, also in excellent agreement with the experimental values of DaBell et al., 4002.5 and 7834 cm−1, respectively. [ABSTRACT FROM AUTHOR]

A theoretical line list for |$^{15}$| NH |$_3$| CoYuTe-15 is presented based on the empirical potential energy and ab initio dipole moments surfaces developed and used for the production of the ExoMol line list CoYuTe for |$^{14}$| NH |$_3$|⁠. The ro-vibrational energy levels and wavefunctions are computed using the variational program trove. The line list ranges up to 10 000 cm |$^{-1}$| (⁠|$\lambda \ge 1$| μ m) and contains 929 795 249 transitions between 1 269 961 states with |$J\le 30$|⁠. The line list should be applicable for temperatures up to |$\sim$| 1000 K. To improve the accuracy of the line positions, a set of experimentally derived energy levels of |$^{15}$| NH |$_3$| is produced using the marvel (Measured Active Rotation Vibration Energy Level) procedure. To this end, 37 experimental sources of the line positions of |$^{15}$| NH |$_3$| available in the literature are collected, combined, and systematized to produce a self-consistent spectroscopic network of 21 095 |$^{15}$| NH |$_3$| transitions covering 40 vibrational bands ranging up to 6818 cm |$^{-1}$| and resulting in 2777 energy term values. These marvel energies are then used to replace the theoretical values in the CoYuTe-15 line list and also complemented by pseudo- marvel energies obtained by an isotopologue extrapolation using the previously reported marvel energies of the |$^{14}$| NH |$_3$| parent isotopologue of ammonia. A list of 53 856 high-resolution transitions between marvel states and theoretical intensities is provided in the HITRAN format. Comparison with the recent experimental spectra of |$^{15}$| NH |$_3$| illustrate the potential of the line list for detections and as an efficient assistant in spectroscopic assignments. The line list is available from www.exomol.com. [ABSTRACT FROM AUTHOR]

In this paper, we study the topological effects of the global monopole spacetime on the energy eigenvalues of spherical symmetric potentials in the nonrelativistic regime. We deal with the radial equation by using the Wentzel, Kramers and Brillouim (WKB) approximation. In the cases where the energy levels of the ℓ -waves can be achieved, the WKB approximation is used based on the Langer transformation. [ABSTRACT FROM AUTHOR]

Bandgap is a key property that determines electrical and optical properties in materials. Modulating the bandgap thus is critical in developing novel materials particularly semiconductors with improved features. This study examines the bandgap, highest occupied molecular orbital (HOMO), and lowest unoccupied molecular orbital (LUMO) energy level trends in a metal organic framework, metal–organic framework 5 (MOF‐5), as a function of Hammett substituent effect (with the constant σm in the meta‐position of the benzene ring) and solvent dielectric effect (with the constant ε). Specifically, experimental design and response surface methodologies helped to assess the significance of trends and correlations between these molecular properties with σm and ε. While the HOMO and LUMO decrease with increasing σm, the LUMO exhibits greater sensitivity to the substituent's electron withdrawing capability. The relative difference in these trends helps to explain why the bandgap tends to decrease with increasing σm. [ABSTRACT FROM AUTHOR]

We show how the quantum hydrodynamical formulation of quantum mechanics converts the nonlocality in the standard wave-like description of quantum systems by an instability of the quantum system, which opens the door to a new way for studying quantum systems based on known methodologies for studying the stability of fluids. As a second result, we show how the Madelung equations describe quantized energies without any external quantization conditions. [ABSTRACT FROM AUTHOR]

A theoretical line list for |$^{15}$| NH |$_3$| CoYuTe-15 is presented based on the empirical potential energy and ab initio dipole moments surfaces developed and used for the production of the ExoMol line list CoYuTe for |$^{14}$| NH |$_3$|⁠. The ro-vibrational energy levels and wavefunctions are computed using the variational program trove. The line list ranges up to 10 000 cm |$^{-1}$| (⁠|$\lambda \ge 1$| μ m) and contains 929 795 249 transitions between 1 269 961 states with |$J\le 30$|⁠. The line list should be applicable for temperatures up to |$\sim$| 1000 K. To improve the accuracy of the line positions, a set of experimentally derived energy levels of |$^{15}$| NH |$_3$| is produced using the marvel (Measured Active Rotation Vibration Energy Level) procedure. To this end, 37 experimental sources of the line positions of |$^{15}$| NH |$_3$| available in the literature are collected, combined, and systematized to produce a self-consistent spectroscopic network of 21 095 |$^{15}$| NH |$_3$| transitions covering 40 vibrational bands ranging up to 6818 cm |$^{-1}$| and resulting in 2777 energy term values. These marvel energies are then used to replace the theoretical values in the CoYuTe-15 line list and also complemented by pseudo- marvel energies obtained by an isotopologue extrapolation using the previously reported marvel energies of the |$^{14}$| NH |$_3$| parent isotopologue of ammonia. A list of 53 856 high-resolution transitions between marvel states and theoretical intensities is provided in the HITRAN format. Comparison with the recent experimental spectra of |$^{15}$| NH |$_3$| illustrate the potential of the line list for detections and as an efficient assistant in spectroscopic assignments. The line list is available from www.exomol.com. [ABSTRACT FROM AUTHOR]

Nonaqueous organic aluminum batteries are considered as promising high‐safety energy storage devices due to stable ionic liquid electrolytes and Al metals. However, the stability and capacity of organic positive electrodes are limited by their inherent high solubility and low active organic molecules. To address such issues, here porphyrin compounds with rigid molecular structures present stable and reversible capability in electrochemically storing AlCl2+. Comparison between the porphyrin molecules with electron‐donating groups (TPP‐EDG) and with electron‐withdrawing groups (TPP‐EWG) suggests that EDG is responsible for increasing both highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels, resulting in decreased redox potentials. On the other hand, EWG is associated with decreasing both HOMO and LUMO energy levels, leading to promoted redox potentials. EDG and EWG play critical roles in regulating electron density of porphyrin π bond and electrochemical energy storage kinetics behavior. The competitive mechanism between electrochemical redox reaction and de/adsorption processes suggests that TPP‐OCH3 delivers the highest specific capacity ~171.8 mAh g−1, approaching a record in the organic Al batteries. [ABSTRACT FROM AUTHOR]

Three functionalized thienopyrazines (TPs), TP‐MN (1), TP‐CA (2), and TPT‐MN (3) were designed and synthesized as self‐assembled monolayers (SAMs) deposited on the NiOx film for tin‐perovskite solar cells (TPSCs). Thermal, optical, electrochemical, morphological, crystallinity, hole mobility, and charge recombination properties, as well as DFT‐derived energy levels with electrostatic surface potential mapping of these SAMs, have been thoroughly investigated and discussed. The structure of the TP‐MN (1) single crystal was successfully grown and analyzed to support the uniform SAM produced on the ITO/NiOx substrate. When we used NiOx as HTM in TPSC, the device showed poor performance. To improve the efficiency of TPSC, we utilized a combination of new organic SAMs with NiOx as HTM, the TPSC device exhibited the highest PCE of 7.7 % for TP‐MN (1). Hence, the designed NiOx/TP‐MN (1) acts as a new model system for the development of efficient SAM‐based TPSC. To the best of our knowledge, the combination of organic SAMs with anchoring CN/CN or CN/COOH groups and NiOx as HTM for TPSC has never been reported elsewhere. The TPSC device based on the NiOx/TP‐MN bilayer exhibits great enduring stability for performance, retaining ~80 % of its original value for shelf storage over 4000 h. [ABSTRACT FROM AUTHOR]

In the landscape of photovoltaic research, carbon‐based perovskite solar cells (C‐PSCs) have attracted widespread attention due to their outstanding stability. However, compared to metal‐based PSCs, their power conversion efficiency (PCE) lags markedly behind. The key lies in two primary factors: First, the inefficiency of the carbon electrode in transporting and collecting carriers; second, the energy level mismatch with adjacent functional layers. These problems increase both the charge transport resistance and the charge injection barriers, thereby diminishing the overall efficiency of the device. In this study, an effective strategy is presented to tackle this issue by developing modular C‐PSCs that utilize dual carbon electrodes and implement multiscale modulation. This approach specifically focuses on three crucial aspects: establishing a highly conductive network, ensuring sufficient interfacial contact, and achieving well‐matched energy band alignment. By synergistically incorporating 0D carbon black (CB) and 1D carbon nanotube (CNT) into dual carbon electrodes, a resilient conductive network with enhanced interfacial contact is established, creating favorable conditions for efficient carrier transfer. Additionally, the energy level structure of CB is meticulously adjusted at the molecular scale by introducing individually adsorbed titanium (Ti) atoms, effectively addressing the energy level mismatch with the hole transport layer (spiro‐OMeTAD), and notably reducing the charge injection barrier at the interface. Based on the above strategy, the PCE of the C‐PSCs has undergone a remarkable enhancement from 15.27% to 22.45%. Moreover, the device shows excellent stability, with its PCE retaining over 95% of the initial value even after 1000 h of continuous operation under one‐sun intensity. [ABSTRACT FROM AUTHOR]

Ambipolar organic electrochemical transistors (OECTs) with a single organic mixed ionic‐electronic conductor (OMIEC) have unique advantages by reducing fabrication complexity and cost in complementary logic circuit and bioelectronic applications. However, the design and synthesis of high‐performance ambipolar OMIECs for efficient transport and coupling both cation/anion and electron/hole remain challenging. Herein, a donor–acceptor (D–A)‐typed ambipolar OMIEC polymer (DHF‐gTT) is presented, whose superior ambipolarity stems from the concurrent oligoethyleneglycol‐functionalized D/A units that facilitates cation/anion injection and transport. Additionally, the fluorination of acceptor unit improves both hole/electron transports due to the fully‐locked backbone and promotes electron injection by down‐shifting molecular energy levels. Consequently, DHF‐gTT‐based OECTs achieve balanced figure‐of‐merit (µC*) for both p‐type and n‐type operations (12.4–14.6 F cm−1 V−1 s−1), setting new benchmarks for ambipolar OECTs, in terms of n‐type µC* and electron/hole mobilities. Such ambipolar OECTs enable the inverter to achieve a record‐high gain (102 V/V) and associated n‐type and p‐type molecular detectors to offer real‐time and highly sensitive detection of histamine and hydrogen peroxide detection, respectively. These results indicate the effectiveness of judicious molecular design on achieving high‐performance ambipolar OMIECs, allowing the state‐of‐the‐art single‐component ambipolar OECTs for both highly integrated logic circuit and bioelectronic applications. [ABSTRACT FROM AUTHOR]

The twisted conformer of bistricyclic aromatic enes (BAEs) has a small HOMO–LUMO gap owing to the twisted double bond. In this study, we synthesized diphenoquinones fused with thiophene rings as a new twisted conformer-predominant BAE. They exhibited deep LUMO energy levels and apparent n-type semiconductor properties. [ABSTRACT FROM AUTHOR]

Summary: In "Internet of Things" (IoT) technology, all objects can connect to the Internet with a unique Internet address. The sensors have limited energy resources due to their use of batteries in supplying energy, and since battery replacement in these sensors is not usually feasible, the longevity of wireless sensor networks is limited. Therefore, reducing the energy consumption of the used sensors in IoT networks to increase the network lifetime is one of the crucial challenges and parameters in such networks. These networks are subject to a variety of errors. Errors in wireless communication channels, network dynamics due to the mobility of nodes, and the potential for mistakes in mobile nodes are among the causes of errors in these networks. Despite the above failures, the development of routing algorithms in IoT‐based networks has become a significant challenge for researchers, so it is essential to provide routing algorithms to increase network lifespan and reduce energy consumption. In this study, a two‐dimensional network‐based architecture for the Internet of Things is presented. The proposed algorithm first organizes the nodes into logical cells and selects nodes in each cell as the cluster head. The cluster head is selected based on the binary Particle Swarm Optimization algorithm. Then, each node sends its collected data to the cluster head. The cluster heads first aggregate the received data and then use a fuzzy method to send the data to the base station. The proposed algorithm uses the remaining energy level parameter, cluster density, and location of each cell using fuzzy system capabilities and the particle swarm algorithm to try to route data with less energy consumption and increase network lifespan. The proposed method is simulated in ns2 software, and for a more accurate evaluation, we compare it with LEACH, Ant‐C, PSO, EABC, and SOA‐CH algorithms. We see that the proposed method performs better than other methods in terms of energy consumption and network lifespan. [ABSTRACT FROM AUTHOR]

Highlights Stab‐resistant armors are important protective gear for the law enforcement officers and security forces. This research attempts to develop stab‐resistant armors for different impact energy levels using multi‐layer neat and shear thickening fluid (STF)‐ treated Kevlar® fabrics. The developed panels were tested using National Institute of Justice's (NIJ) P1 knife at wide range of stabbing energy from 6 to 36 J. The panel containing 16 layers of STF‐treated Kevlar® fabric met the requirements at normal and over‐test conditions showing penetration depth lower than 7 and 20 mm, respectively. For stabbing at high energy level (≥ 24 J), the effect of number of Kevlar® fabric layers was found to be highly beneficial in case of STF‐treated condition and not so for the neat one. STF treatment reduced the stab penetration depth by 40%–68% at 24–36 J energy level without any increase in effective weight of the panel. The fabric‐knife interaction was also studied using a novel sharpness tester and optical microscopy. It was found that the tip of knife deformes and sharpness declines at a faster rate in case of STF‐treated fabric. The study opens up possibilities to explore other materials that would damage the tip of knife during stabbing ensuring better protection. Stab resistant armor has been developed for different energy levels. Effect of number of neat fabric layers is less pronounced at higher energy levels. STF can reduce the penetration depth significantly at high energy levels. Silica particles damage the knife tip during stabbing. STF‐treated panels are lighter and efficacious than their neat counterparts. [ABSTRACT FROM AUTHOR]

This study investigates the radiation shielding properties of glass samples within the xGd2O3‐5SiO2‐40Na2O‐(54.5‐x) B2O3:0.5CeF3 composition, where x varies from 0 to 10 mol.%, which is coded as GSNBCX (X = 1, 2, 3, and 4). The assessment is done through comprehensive Monte Carlo simulation and Phy‐X/PSD software analyses. The primary objective of this study is to comprehensively evaluate the radiation shielding properties of glass compositions with varying Gd2O3 concentrations. This evaluation encompasses both the attenuation of gamma radiation within the broad energy range of 0.015 MeV to 15 MeV and the assessment of fast neutron removal cross sections, with a specific focus on simulations spanning energy levels from 0.5 to 10 MeV. By examining these parameters, we aim to elucidate the impact of Gd2O3 concentration on the material's overall effectiveness in radiation shielding applications. The results reveal a significant variation in the mass attenuation coefficient (μm) across the investigated glass samples. For instance, μm values range from 3.244 to 0.019 cm2·g−1 for GSNBC1, 20.471 to 0.025 cm2·g−1 for GSNBC2, 27.245 to 0.027 cm2·g−1 for GSNBC3, and 32.223 to 0.029 cm2·g−1 for GSNBC4. Notably, GSNBC4, characterized by a substantial Gd2O3 concentration (10 mol.%), exhibits the highest values of both μm and linear attenuation coefficient (μ). Furthermore, the investigation delves into the fast neutron removal cross section (FNRCS), which displays values of 0.97, 0.95, 0.094, and 0.93 cm−1, respectively. GSNBC1, marked by its elevated B2O3 content (54.5 mol.%), showcases the highest FNRCS. These findings underscore the efficacy of Gd2O3‐doped materials in shielding against gamma rays, holding promise for various applications in radiation protection, particularly in the medical and nuclear sectors. This study contributes valuable insights into developing effective radiation‐blocking materials for diverse industrial and scientific contexts. [ABSTRACT FROM AUTHOR]

Large‐area organic photovoltaic modules have a wide range of applications in a number of fields due to their unique advantages. Inverted organic solar cells exhibit better air stability and are suitable for all‐air printing of large‐area modules. However, the mismatch between the surface energy of ZnO and the active layer leads to coffee rings and stick‐slip effects during the printing process, resulting in uneven deposition of the active layer. Additionally, the mismatch in energy levels between the active layer and ZnO degrades device performance. Hence, a phenol series of alcohol solutions is utilized to improve the wettability and surface energy of ZnO, enabling the formation of large‐area homogeneous active layer films. Hydroxyl groups in the phenol series passivate ZnO surface defects and form hydrogen bonds with small molecules of the acceptor, increasing carrier mobility and improving device performances. Based on the PM6: BTP‐eC9 (o‐XY) system, the power conversion efficiency (PCE) reaches 18.80% for small‐area devices and 15.87% for large‐area modules, higher than the forward structure (15.83%). This study offers an effective approach to mitigating large‐area active layer film uniformity issues, advancing the preparation of large‐area organic photovoltaic modules via all‐air printing. [ABSTRACT FROM AUTHOR]

In recent years, catalytic degradation driven by mechanical‐energy tribocatalysis has gained much attention. Point defects play very important on the catalytic activity of ferroelectric oxides. In this study, we focus on the influence of oxygen vacancies on the catalyst performance of ferroelectric oxide KSr2Nb4TaO15 (KSNT) with a tetragonal tungsten bronze structure. The concentration of oxygen vacancies is modified by sintering atmosphere. The KSNT sintered in N2 atmosphere exhibits the best tribocatalytic degradation efficiency of 96.7% within 2 h for degradation rhodamine B due to high concentration of oxygen vacancies. The excellent degradation efficiency is attributed to the defect energy level of KSNT and high electron–hole separation efficiency. This work reveals the relationship between oxygen vacancies and tribocatalysis efficiency, which is helpful to design and modify the new ferroelectric oxides for tribocatalysis. [ABSTRACT FROM AUTHOR]

Upconversion luminescence presents obvious advantages in optical temperature sensing, nevertheless the application in complex scenarios is limited by luminescence thermal quenching. Herein, NaYS 2 :Yb3+,Nd3+ phosphors are synthesized by the solid-gas reaction method and used for temperature sensing. A series of emissions for Nd3+ from visible to near-infrared region are achieved based on energy transfer from Yb3+ to Nd3+ under 980 nm excitation. With elevating the temperature, significant thermal enhancement effect of nearly three orders of magnitude is detected in near-infrared emission of 4F 7/2 → 4I 9/2 , which is attributed to phonon-assisted energy transfer of Yb3+→Nd3+ and the corresponding thermal population effect. The thermal behaviors of thermally coupled energy levels for 4G 7/2 /2G 9/2 and 4F 7/2 /4F 5/2 in NaYS 2 :Yb3+,Nd3+ are evaluated by luminescence intensity ratio technique. Remarkably, the optical thermometer based on the enhanced emission of 4F 7/2 /4F 5/2 shows excellent temperature measurement performance, which is expected to be applied in wide-temperature-range and highly-sensitive temperature sensing. These results not only provide a pathway to realize high performance temperature sensing, but also heighten the understanding of UC emission thermal enhancement. [ABSTRACT FROM AUTHOR]

Ternary metal oxide materials are being explored as potential electrode materials for dye-sensitized solar cells due to their adjustable electronic band structures through elemental composition modifications. Perovskite materials based on zinc and titanium have been utilised in DSSC and show moderate performance. Considerable research has been dedicated to this field to improve their performances. The focus was primarily on the synthetic variabilities due to their impact on performance under varying synthetic conditions. According to this perspective, no comparative studies have found superior methodologies for utilising zinc titanate as a potential photoanode in DSSC. We synthesised a zinc titanate material using thermal, sol-gel, and plasma irradiation techniques. The materials' structural variability was analysed using PXRD and FT-IR techniques. A mixed-phase composition of spinel cubic and hexagonal has been identified. The SEM images provide insights into the particle distribution and morphology of the zinc titanate materials. Investigating absorption properties, band gap energy levels and aggregation behaviours provided initial insights into the potential use of the three zinc titanate materials. The DSSC devices were fabricated using zinc titanate materials with varying properties, and the results are detailed in this discussion. Based on the findings, the plasma and thermal irradiation techniques yielded more favourable zinc titanate materials for dye-sensitized solar cell use. The efficiency reached 0.04 % when operating with polymeric gel electrolytes. [Display omitted] [ABSTRACT FROM AUTHOR]

The Li3LaMgTiO6 phosphor doped with Mn4+ was synthesized using the solid phase gradient temperature technique. The micro-structure and spectral properties were characterized through XRD and fluorescence spectrum analysis. The experimental results demonstrate that it exhibits a typical layered structure, and the gradient temperature technique can effectively modify and distort the crystal cell structure from tetrahedral to cubic system. This transformation alters the required octahedral structure for Mn4+, resulting in the splitting of 2A levels into 2Eg and 2T1, thereby enlarging the energy level spacing. Consequently, due to reduced non-radiative transition probability of 2T1 → 2Eg, a blue shift phenomenon will be formed in the fluorescence peak. By utilizing a 358 nm LED as a pump source, we observed this phenomenon in fluorescence peaks from 711 to 680 nm. Furthermore, by adjusting the gradient temperature zone, it is possible to obtain a full-width half-maximum (FWHM) rectangular fluorescence spectrum up to 100 nm with excellent homogeneity of light intensity, which holds great promise for applications in opto-electronics and crop fields. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) and M13 bacteriophage can self-assemble to form ultra-low density porous structures, known as GraPhage13 aerogels (GPA). Due to the insulating nature of GPA and the challenges in producing highly conductive aerogels, it is paramount to explore ways to enhance the conductivity of GPA. Herein, we have developed a method to enhance the conductivity of GPA, via the integration and optimisation of 5 nm and 20 nm diameter gold nanoparticles (AuNPs) into the aerogel structure and systematically analysed the morphology, composition and spectroscopic properties of the resulting GPA-Au nanocomposite. The fabricated GPA-Au nanocomposites exhibited remarkable increases in conductivity, with the integration of 5 nm AuNPs leading to a 53-fold increase compared to GPA, achieving a performance of up to 360 nS/cm, which is within the range suitable for miniaturised semiconductor devices. The mechanism behind the conductivity enhancement was further investigated and attributed to GO-AuNP interactions increasing the carrier density by introducing new energy levels in the GO band gap or shifting its Fermi level towards the conduction band. These findings demonstrate the potential of functionalised AuNPs to significantly improve the electrical properties of GPA, paving the way for their application in gas sensors for biological and chemical detection and a new range of advanced semiconductor devices. [ABSTRACT FROM AUTHOR]

We extend the scattering theory of the Josephson effect to include a coupling of the Josephson junction to a gapless electron reservoir in the normal state. By opening up the system with a quasiparticle escape rate 1 / τ , the supercurrent carried at zero temperature by an Andreev level at energy ε A is reduced by a factor (2 / π) arctan (2 ε A τ / ℏ). We make contact with recent work on "non-Hermitian Josephson junctions," by comparing this result to different proposed generalizations of the Josephson effect to non-Hermitian Hamiltonians. [ABSTRACT FROM AUTHOR]

We present the formation of a composite film made out of formamidinium lead iodide (FAPI) and molybdenum disulphide quantum dots (MoS2 QDs) and propose a corresponding photovoltaic device architecture based on a 'type-I' alignment of the two materials' electronic energy levels. The introduction of the MoS2 QDs has not compromised the overall crystallinity of the FAPI film and the composite absorber has shown improved stability. We report on the benefits of this composite film and energy band arrangement as the photogenerated carriers in MoS2 QDs, both positive and negative, are injected into the FAPI host matrix, resulting in an increased current density of 24.19 mA cm−2 compared to a current density of 19.83 mA cm−2 for the control device with FAPI only. The corresponding photoconversion efficiency increases from 12.6 to 15.0%. We also show that inclusion of MoS2 QDs in FAPI films resulted in a notable improvement in the fill factor and open-circuit voltage of the solar cells. Most importantly, MoS2 QDs enhanced the film stability by reducing defect formation and acting as passivating agents that minimize recombination losses and improve charge carrier transport. Our results suggest that a composite film in a type-I device architecture can introduce benefits for both future developments in perovskite solar cells and effectively tackling the longstanding challenges of carrier transport in QDs solar cells. [ABSTRACT FROM AUTHOR]

The development of microcrystalline glass‐ceramics with high transparency and deep trap energy levels is crucial for the cost‐effective and large‐scale production of scintillators and optical data storage applications. In this study, the incorporation of highly electronegative divalent tin (Sn2+) plays a key role in modulating the network structure of borate glass. This leads to the successful synthesis of SrAl2O4:Eu2+ microcrystalline glass with high transparency, reaching up to 80%, and excellent crystallinity. Additionally, a series of non‐optically active ions with different valence states is co‐doped with Eu2+ to fine‐tune the trap levels of the SrAl2O4 microcrystals. All samples maintain high crystallinity and exhibit good transparency. In particular, the Pb2+ ion co‐doped samples achieve an increased trap energy level of 1.28 eV, significantly enhancing their capacity to capture X‐rays and ultraviolet light. Density functional theory calculations reveal that this enhancement is due to severe lattice distortion caused by Pb2+ ions occupying interstitial sites in SrAl2O4. Utilizing the SrAl2O4:Eu2+, Pb2+ glass‐ceramics materials, X‐ray imaging with a delay of up to 210 s and optical information storage for >60 d is achieved. This study provides valuable insights into the crystal growth and trap modulation of persistent luminescent materials within a three‐dimensional glass network structure. [ABSTRACT FROM AUTHOR]