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Organic–inorganic hybrid perovskite quantum wells exhibit electronic structures with properties intermediate between those of inorganic semiconductors and molecular crystals. In these systems, periodic layers of organic spacer molecules occupy the interstitial spaces between perovskite sheets, thereby confining electronic excitations to two dimensions. Here, we investigate spectroscopic line broadening mechanisms for phonons coupled to excitons in lead-iodide layered perovskites with phenyl ethyl ammonium (PEA) and azobenzene ethyl ammonium (AzoEA) spacer cations. Using a modified Elliot line shape analysis for the absorbance and photoluminescence spectra, polaron binding energies of 11.2 and 17.5 meV are calculated for (PEA)2PbI4 and (AzoEA)2PbI4, respectively. To determine whether the polaron stabilization processes influence the dephasing mechanisms of coupled phonons, five-pulse coherent Raman spectroscopies are applied to the two systems under electronically resonant conditions. The prominence of inhomogeneous line broadening mechanisms detected in (AzoEA)2PbI4 suggests that thermal fluctuations involving the deformable organic phase broaden the distributions of phonon frequencies within the quantum wells. In addition, our data indicate that polaron stabilization primarily involves photoinduced reorganization of the organic phases for both systems, whereas the impulsively excited phonons represent less than 10% of the total polaron binding energy. The signal generation mechanisms associated with our fifth-order coherent Raman experiments are explored with a perturbative model in which cumulant expansions are used to account for time-coincident vibrational dephasing and polaron stabilization processes. [ABSTRACT FROM AUTHOR]

We consider the electron stimulated desorption, via dissociative electron attachment, of anionic species from thin condensed CD4 films deposited on a Pt substrate and compare experimentally observed desorption yields with density functional theory calculations of the binding energies of various anionic and neutral moieties to Pt(111). Certain species (which can be considered chemisorbed) exhibit very high binding energies and large charge transfer with the substrate. Other "physisorbed" species have much lower binding energies. Species that chemisorb have lower desorption yields than those that physisorb, especially at 1–2 monolayer coverage of the Pt substrate. The binding energy of D− to Pt is the weakest, and experimentally, the desorption yield is the highest regardless of the thickness of CD4. The calculations show that the formation and desorption of anionic species at a distance of 16 Å from the substrate, which is equivalent to the thickness of CD4 films of four monolayers, are not influenced by the short-range interactions between the substrate and the molecule and DEA products. [ABSTRACT FROM AUTHOR]

Using the density-functional theory approach, including Hubbard U correction, we investigate the defect structures consisting of vanadium (V) atoms embedded in a monolayer silicene. Specifically, we consider V–V atom pairs in antiferromagnetic (AFM), ferromagnetic (FM), and non-magnetic states, which are embedded in substitutional and interstitial sites. We determine the ground-state structures, formation and binding energies, electronic structures, induced magnetization, as well as the spin-exchange coupling between the V–V pair. For the substitutional vanadium atom pair, the stability of the AFM and FM spin configurations depends on the sublattice sites in which the V atoms are sited. When the V pair is located on a similar sublattice site type, the AFM spin alignment is more energetically favored, whereas when the pair is located in a different sublattice site, the FM interactions are more stable. However, the relative stability of the AFM or FM configurations changes rapidly as the separation between the V pair increases. Regarding the interstitial-hole V–V pair configurations, the most stable structure is when the pair is at the nearest-neighbor hole sites and is in an FM alignment. Also, at larger separations, the AFM or FM hole configurations are approximately degenerate in energy. Furthermore, we elucidate on the Ruderman–Kittel–Kasuya–Yosida, direct-exchange, and the superexchange interaction mechanisms in the vanadium-embedded silicene. In addition, we estimate a Curie temperature (Tc) of up to ∼500 K for a silicene structure containing a V pair in the FM spin alignment. Such a high Tc, in addition to the stability of the material, suggests that vanadium-embedded silicene is a potential candidate material for spintronic device applications. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) Sn-based perovskites exhibit significant potential in diverse optoelectronic applications, such as on-chip lasers and photodetectors. Yet, the underlying mechanism behind the frequently observed dual-peak emission in 2D Sn-based perovskites remains a subject of intense debate, and there is a lack of research on the carrier dynamics in these materials. In this study, we investigate these issues in a representative 2D Sn-based perovskite, namely, PEA2SnI4, through temperature-, excitation intensity-, angle-, and time-dependent photoluminescence studies. The results indicate that the high- and low-energy peaks originate from in-face and out-of-face dipole transitions, respectively. In addition, we observe an anomalous increase in the non-radiative recombination rate as temperature decreases. After ruling out enhanced electron–phonon coupling and Auger recombination as potential causes of the anomalous carrier dynamics, we propose that the significantly increased exciton binding energy (Eb) plays a decisive role. The increased Eb arises from enhanced electronic localization, a consequence of weakened lattice distortion at low temperatures, as confirmed by first-principles calculations and temperature-dependent x-ray diffraction measurements. These findings offer valuable insights into the electronic processes in the unique 2D Sn-based perovskites. [ABSTRACT FROM AUTHOR]

The random-phase approximation (RPA) includes a subset of higher than second-order correlation-energy contributions, but stays in the same complexity class as the second-order Møller–Plesset perturbation theory (MP2) in both Gaussian-orbital and plane-wave codes. This makes RPA a promising ab initio electronic structure approach for the binding energies of molecular crystals. Still, some issues stand out in practical applications of RPA. Notably, compact clusters of nonpolar molecules are poorly described, and the interaction energies strongly depend on the reference single-determinant state. Using the many-body expansion of the binding energy of a crystal, we investigate those issues and the effect of beyond-RPA corrections. We find the beneficial effect of quartic-scaling exchange and non-ring coupled-cluster doubles corrections. The nonadditive interactions in compact trimers of molecules are improved by using the self-consistent Hartree–Fock orbitals instead of the usual Kohn–Sham states, but this kind of orbital input also leads to underestimated dimer energies. Overall, a substantial improvement over the RPA with a renormalized singles approach is possible at a modest quartic-scaling cost, which encourages further research into additional RPA corrections. [ABSTRACT FROM AUTHOR]

We use molecular dynamics simulations to examine the homogeneous nucleation of ice VII from metastable liquid water. An unsupervised machine learning classification identifies two distinct local structures composing Ice VII nuclei. The seeding method, combined with the classical nucleation theory (CNT), predicts the solid–liquid interfacial free energy, consistent with the value from the mold integration method. Meanwhile, the nucleation rates estimated from the CNT framework and brute force spontaneous nucleations are inconsistent, and we discuss the reasons for this discrepancy. Structural and dynamical heterogeneities suggest that the potential birthplace for an ice VII embryo is relatively ordered, although not necessarily relatively immobile. Moreover, we demonstrate that without the formation of hydrogen-bond links, ice VII embryos do not grow. [ABSTRACT FROM AUTHOR]

The isotope shifts in electron affinities of Pb were measured by Walter et al. [Phys. Rev. A 106, L010801 (2022)] to be −0.002(4) meV for 207–208Pb and −0.003(4) meV for 206–208Pb by scanning the threshold of the photodetachment channel Pb− ( S 3 / 2 ◦ 4 ) − Pb (3P0), while Chen and Ning reported 0.015(25) and −0.050(22) meV for the isotope shifts on the binding energies measured relative to 3P2 using the SEVI method [J. Chem. Phys. 145, 084303 (2016)]. Here we revisited these isotope shifts by using our second-generation SEVI spectrometer and obtained −0.001(15) meV for 207–208Pb and −0.001(14) meV for 206–208Pb, respectively. In order to aid the experiment by theory, we performed the first ab initio theoretical calculations of isotope shifts in electron affinities and binding energies of Pb, as well as the hyperfine structure of 207Pb−, by using the MCDHF and RCI methods. The isotope shifts in electron affinities of 207–208Pb and 206–208Pb are −0.0023(8) and −0.0037(13) meV for the 3P0 channel, respectively, in good agreement with Walter et al.'s measurements. The isotope shifts in binding energies relative to 3P1,2, −0.0015(8) and −0.0026(13) meV for 207–208Pb and 206–208Pb, respectively, are compatible with the present measurements. The hyperfine constant for the ground state of 207Pb− obtained by the present calculations, A ( S 3 / 2 ◦ 4 ) = − 1118 MHz, differs by a factor of 3 from the previous estimation by Bresteau et al. [J. Phys. B: At., Mol. Opt. Phys. 52, 065001 (2019)]. The reliability is supported by the good agreement between the theoretical and experimental hyperfine parameters of 209Bi. [ABSTRACT FROM AUTHOR]

CNDOL is an a priori, approximate Fockian for molecular wave functions. In this study, we employ several modes of singly excited configuration interaction (CIS) to model molecular excitation properties by using four combinations of the one electron operator terms. Those options are compared to the experimental and theoretical data for a carefully selected set of molecules. The resulting excitons are represented by CIS wave functions that encompass all valence electrons in the system for each excited state energy. The Coulomb–exchange term associated to the calculated excitation energies is rationalized to evaluate theoretical exciton binding energies. This property is shown to be useful for discriminating the charge donation ability of molecular and supermolecular systems. Multielectronic 3D maps of exciton formal charges are showcased, demonstrating the applicability of these approximate wave functions for modeling properties of large molecules and clusters at nanoscales. This modeling proves useful in designing molecular photovoltaic devices. Our methodology holds potential applications in systematic evaluations of such systems and the development of fundamental artificial intelligence databases for predicting related properties. [ABSTRACT FROM AUTHOR]

The isotope shifts in electron affinities of Pb were measured by Walter et al. [Phys. Rev. A 106, L010801 (2022)] to be −0.002(4) meV for 207–208Pb and −0.003(4) meV for 206–208Pb by scanning the threshold of the photodetachment channel Pb− ( S 3 / 2 ◦ 4 ) − Pb (3P0), while Chen and Ning reported 0.015(25) and −0.050(22) meV for the isotope shifts on the binding energies measured relative to 3P2 using the SEVI method [J. Chem. Phys. 145, 084303 (2016)]. Here we revisited these isotope shifts by using our second-generation SEVI spectrometer and obtained −0.001(15) meV for 207–208Pb and −0.001(14) meV for 206–208Pb, respectively. In order to aid the experiment by theory, we performed the first ab initio theoretical calculations of isotope shifts in electron affinities and binding energies of Pb, as well as the hyperfine structure of 207Pb−, by using the MCDHF and RCI methods. The isotope shifts in electron affinities of 207–208Pb and 206–208Pb are −0.0023(8) and −0.0037(13) meV for the 3P0 channel, respectively, in good agreement with Walter et al.'s measurements. The isotope shifts in binding energies relative to 3P1,2, −0.0015(8) and −0.0026(13) meV for 207–208Pb and 206–208Pb, respectively, are compatible with the present measurements. The hyperfine constant for the ground state of 207Pb− obtained by the present calculations, A ( S 3 / 2 ◦ 4 ) = − 1118 MHz, differs by a factor of 3 from the previous estimation by Bresteau et al. [J. Phys. B: At., Mol. Opt. Phys. 52, 065001 (2019)]. The reliability is supported by the good agreement between the theoretical and experimental hyperfine parameters of 209Bi. [ABSTRACT FROM AUTHOR]

Loading of WS2 can greatly improve water splitting H2 generation efficiency of CdS in experiments. Here, we constructed WS2/CdS(100) and WS2/CdS(110) heterostructures with smaller mismatches and explored their interaction energy and band offset by first-principles calculations. Our calculation suggests that the WS2/CdS(100) interface with a stronger binding energy is more active in experiments, while the WS2/CdS(110) interface is metastable. The band alignment between CdS and WS2 is highly dependent on the orientation of the interfaces, and WS2/CdS(100) and WS2/CdS(110) belong to type-I and type-II band alignments, respectively. Therefore, a metal electrode and hole scavenger may be essential in experiments to help WS2/CdS(100) efficiently trap electrons, and a suitable substrate and an appropriate growth temperature are also needed to composite the CdS(110) surface to achieve a higher photocatalytic efficiency. In addition, we performed a detailed analysis of the macroscopic average potential and found that the calculated accuracy of potential difference across the heterostructures due to slab thickness is less than 80 meV at WS2/CdS interfaces. In total, our calculations not only explain the physical reasons for the increased efficiency of WS2/CdS, but also provide a detailed guideline for the design of a more efficient synergistic catalyst. [ABSTRACT FROM AUTHOR]

Layered superatomic semiconductors, whose building blocks are atomically precise molecular clusters, exhibit interesting electronic and vibrational properties. In recent work [Tulyagankhodjaev et al., Science 382, 438 (2023)], transient reflection microscopy revealed quasi-ballistic exciton dynamics in Re6Se8Cl2, which was attributed to the formation of polarons due to coupling with acoustic phonons. Here, we characterize the electronic, excitonic, and phononic properties with periodic density functional theory. We further parameterize a polaron Hamiltonian with nonlocal (Su–Schrieffer–Heeger) coupling to an acoustic phonon to study the polaron ground state binding energy and dispersion relation with variational wavefunctions. We calculate a polaron binding energy of about 10 meV at room temperature, and the maximum group velocity of our polaron dispersion relation is 1.5 km/s, which is similar to the experimentally observed exciton transport velocity. [ABSTRACT FROM AUTHOR]

Layered superatomic semiconductors, whose building blocks are atomically precise molecular clusters, exhibit interesting electronic and vibrational properties. In recent work [Tulyagankhodjaev et al., Science 382, 438 (2023)], transient reflection microscopy revealed quasi-ballistic exciton dynamics in Re6Se8Cl2, which was attributed to the formation of polarons due to coupling with acoustic phonons. Here, we characterize the electronic, excitonic, and phononic properties with periodic density functional theory. We further parameterize a polaron Hamiltonian with nonlocal (Su–Schrieffer–Heeger) coupling to an acoustic phonon to study the polaron ground state binding energy and dispersion relation with variational wavefunctions. We calculate a polaron binding energy of about 10 meV at room temperature, and the maximum group velocity of our polaron dispersion relation is 1.5 km/s, which is similar to the experimentally observed exciton transport velocity. [ABSTRACT FROM AUTHOR]

3,4-bis(3-nitrofurazan-4-yl) furoxan (DNTF) is one of the third-generation energetic compounds with excellent comprehensive properties, which can be added to polymer bonded explosive (PBX) to improve energy levels and regulate sensitivity, so the compatibility of DNTF with other components in PBX, especially the binder, is the first question. Herein, two typical hydrocarbon polymers commonly used in PBX, which are hydroxyl-terminated polybutadiene (HTPB) and polyisobutylene (PIB), were selected as the binder, and the compatibility of HTPB and PIB with DNTF was investigated by differential scanning calorimetry (DSC), the vacuum stability test (VST), and in situ infrared spectroscopy (in situ IR). The results of compatibility experiments were verified by using the binding energy and solubility parameter criteria in molecular dynamics (MD). Experimental and MD simulation results showed that DNTF could be compatible with PIB but incompatible with HTPB. The frontier molecular orbital theory in quantum chemistry (QC) was adopted to explore the frontier orbital electron distribution and energy levels of DNTF/HTPB and DNTF/PIB composite systems to better understand the microscopic compatibility mechanism. The compatibility results of the two composite systems were explained from the perspective of electron transfer. All these can deduce that a hydrocarbon polymer binder with a saturated carbon–hydrogen bond at the end of the molecular chain has good compatibility with DNTF, compared with a hydroxyl group, which has bad compatibility with DNTF. [ABSTRACT FROM AUTHOR]

We present fully coupled, full-dimensional quantum calculations of the inter- and intra-molecular vibrational states of HCl trimer, a paradigmatic hydrogen-bonded molecular trimer. They are performed utilizing the recently developed methodology for the rigorous 12D quantum treatment of the vibrations of the noncovalently bound trimers of flexible diatomic molecules [Felker and Bačić, J. Chem. Phys. 158, 234109 (2023)], which was previously applied to the HF trimer by us. In this work, the many-body 12D potential energy surface (PES) of (HCl)3 [Mancini and Bowman, J. Phys. Chem. A 118, 7367 (2014)] is employed. The calculations extend to the intramolecular HCl-stretch excited vibrational states of the trimer with one- and two-quanta, together with the low-energy intermolecular vibrational states in the two excited v = 1 intramolecular vibrational manifolds. They reveal significant coupling between the intra- and inter-molecular vibrational modes. The 12D calculations also show that the frequencies of the v = 1 HCl stretching states of the HCl trimer are significantly redshifted relative to those of the isolated HCl monomer. Detailed comparison is made between the results of the 12D calculations on the two-body PES, obtained by removing the three-body term from the original 2 + 3-body PES, and those computed on the 2 + 3-body PES. It demonstrates that the three-body interactions have a strong effect on the trimer binding energy as well as on its intra- and inter-molecular vibrational energy levels. Comparison with the available spectroscopic data shows that good agreement with the experiment is achieved only if the three-body interactions are included. Some low-energy vibrational states localized in a secondary minimum of the PES are characterized as well. [ABSTRACT FROM AUTHOR]

Density functional approximations to the exchange–correlation energy can often identify strongly correlated systems and estimate their energetics through energy-minimizing symmetry-breaking. In particular, the binding energy curve of the strongly correlated chromium dimer is described qualitatively by the local spin density approximation (LSDA) and almost quantitatively by the Perdew–Burke–Ernzerhof generalized gradient approximation (PBE-GGA), where the symmetry breaking is antiferromagnetic for both. Here, we show that a full Perdew–Zunger self-interaction-correction (SIC) to LSDA seems to go too far by creating an unphysical symmetry-broken state, with effectively zero magnetic moment but non-zero spin density on each atom, which lies ∼4 eV below the antiferromagnetic solution. A similar symmetry-breaking, observed in the atom, better corresponds to the 3d↑↑4s↑3d↓↓4s↓ configuration than to the standard 3d↑↑↑↑↑4s↑. For this new solution, the total energy of the dimer at its observed bond length is higher than that of the separated atoms. These results can be regarded as qualitative evidence that the SIC needs to be scaled down in many-electron regions. [ABSTRACT FROM AUTHOR]

This study focuses on the recognition and isolation of fullerenes, which are crucial for further exploration of their physical and chemical properties. Our goal is to investigate the potential recognition of the D5h–C70 fullerene using crown-shaped metal compositions through density functional theory calculations. We assess the effectiveness of fullerene C70 recognition by studying the binding energy. Additionally, various analyses were conducted, including natural bond order charge analysis and reduced density gradient analysis, to understand the interaction mechanism between the host and guest molecules. These investigations provide valuable insights into the nature of the interaction and the stability of the host–guest system. To facilitate the release of the fullerene guest molecule, the vis–NIR spectra were simulated for the host–guest structures. This analysis offers guidance on the specific wavelengths that can be utilized to release the fullerene guest from the host–guest structures. Overall, this work proposes a new strategy for the effective recognition of various fullerene molecules and their subsequent release from host–guest systems. These findings could potentially be applied in assemblies involving fullerenes, advancing their practical applications. [ABSTRACT FROM AUTHOR]

This study focuses on the recognition and isolation of fullerenes, which are crucial for further exploration of their physical and chemical properties. Our goal is to investigate the potential recognition of the D5h–C70 fullerene using crown-shaped metal compositions through density functional theory calculations. We assess the effectiveness of fullerene C70 recognition by studying the binding energy. Additionally, various analyses were conducted, including natural bond order charge analysis and reduced density gradient analysis, to understand the interaction mechanism between the host and guest molecules. These investigations provide valuable insights into the nature of the interaction and the stability of the host–guest system. To facilitate the release of the fullerene guest molecule, the vis–NIR spectra were simulated for the host–guest structures. This analysis offers guidance on the specific wavelengths that can be utilized to release the fullerene guest from the host–guest structures. Overall, this work proposes a new strategy for the effective recognition of various fullerene molecules and their subsequent release from host–guest systems. These findings could potentially be applied in assemblies involving fullerenes, advancing their practical applications. [ABSTRACT FROM AUTHOR]

We modify the reweighting factor of the projector used in diffusion Monte Carlo to reduce the time-step error of the total energy. Furthermore, we present a reweighting scheme that has the desirable feature that it is exactly size-consistent, i.e., the energy of a system containing widely separated fragments is the same as the sum of the energies of the individual fragments. The practical utility of the latter improvement is that it reduces the time-step error of the binding energies of some weakly interacting systems. [ABSTRACT FROM AUTHOR]

We examine the optical and electronic properties of a GaAs spherical quantum dot with a hydrogenic impurity in its center. We study two different confining potentials: (1) a modified Gaussian potential and (2) a power-exponential potential. Using the finite difference method, we solve the radial Schrodinger equation for the 1s and 1p energy levels and their probability densities and subsequently compute the optical absorption coefficient (OAC) for each confining potential using Fermis golden rule. We discuss the role of different physical quantities influencing the behavior of the OAC, such as the structural parameters of each potential, the dipole matrix elements, and their energy separation. Our results show that modification of the structural physical parameters of each potential can enable new optoelectronic devices that can leverage inter-sub-band optical transitions.

An in‐depth investigation of transition metal impurities (Hf, Zr, Nb, and W) is presented as shallow donors in monoclinic Ga2O3 using first‐principles calculations within the framework of density functional theory. A combination of semilocal and hybrid functionals is used to predict their binding energies and hyperfine parameters. The generalized gradient approximation (GGA) allows performing calculations for supercells of up to 2500 atoms, enabling an extrapolation to the dilute limit. The shortcoming of GGA in correctly describing the electron localization is then overcome by the use of the hybrid functional. Results are presented and discussed in light of the application of these transition‐metal elements as shallow donors in Ga2O3 and their identification in the experiment. The methodology applied here can be used in calculations for shallow donors in other systems.

This study examines the structures, energies, and IR vibrational spectra of the sulfur dioxide–water SO2(H2O) complexes by employing coupled cluster theory CCSD(T) with Dunning style correlation consistent type basis sets aug-cc-pV(n+d)Z (n = D, T, Q, 5). Complete basis set (CBS) extrapolations have been carried out to predict binding energies for two isomers of the SO2(H2O) complex: a stacked global minimum (1A) structure and a hydrogen-bonded local minimum (1B) structure. The CCSD(T)/CBS extrapolation predicts an intermolecular S–O distance rS⋯O = 2.827 Å for the stacked isomer, which is in excellent agreement with an experimental measurement of 2.824 Å [K. Matsumura et al., J. Chem. Phys., 91, 5887 (1989)]. The CCSD(T)/CBS binding energy for the stacked dimer 1A and hydrogen-bonded form 1B is De = −4.37 kcal/mol and De = −2.40 kcal/mol, respectively. This study also employs anharmonic VPT2 MP2/aug-cc-pV(n+d)Z level corrections to CCSD(T)/aug-cc-pV(n+d)Z vibrational frequencies in both forms of SO2(H2O). The anharmonic CCSD(T)/aug-cc-pV(Q+d)Z OH stretching frequencies in the stacked structure 1A are 3743 cm−1 (ν3) and 3647 cm−1 (ν1), and these align well with the recorded IR spectroscopic values of 3745 and 3643 cm−1, respectively [C. Wang et al., J. Phys. Chem. Lett., 13, 5654 (2022)]. If we combine CCSD(T)/aug-cc-pV(n+d)Z De values with VPT2 vibrational frequencies, we obtain a new CCSD(T)/aug-cc-pV(Q+d)Z anharmonic dissociation energy D0 = −3.48 kcal/mol for 1A and D0 = −1.74 kcal/mol for 1B. In summary, the results presented here demonstrate that the application of CCSD(T) calculations with aug-cc-pV(n+d)Z basis sets and CBS extrapolations is critical in probing the structure and IR spectroscopic properties of the sulfur dioxide–water complex. [ABSTRACT FROM AUTHOR]

The role of strain in material properties is well-established, serving as a tool for altering atomic positions and defect formation, adjusting electronic structures and lattice vibrations, and influencing phase transitions, physical characteristics, and chemical properties. In this study, we conducted theoretical calculations of the binding energy and photoionization cross section (PCS) within a spherical core/shell quantum dot (CSQD) for the different transitions between the ground state of a donor impurity and the four low-lying conduction band states. During our study, we employed the finite element method to determine the energy levels and wave functions of the system within the effective mass approximation. Subsequently, we investigated the changes in PCS and binding energy while varying shell width under the influence of an applied electric field, considering both cases with and without the effect of strain. The strain effect was incorporated based on Hooke's law, and we developed specific expressions and utilized the continuum linear elasticity mechanical model for a single spherically symmetric shell. The results demonstrate that the strain correction enhances the binding energy of the four low-lying energy levels, leading to a shift of the PCS peaks toward higher energies. Conversely, the application of an external electric field has varying effects depending on the specific transition being considered. We compared our theoretical results with available experimental data and found them to be in good agreement. The pronounced blue-shift and substantial enhancement in magnitude of PCS spectra concerning shell width, electric field, and strain make CSQDs highly promising candidates for applications in adjustable nano-optoelectronic devices. [ABSTRACT FROM AUTHOR]

The electronic properties of SO2 at the surface of a water cluster were investigated by employing a combination of Born–Oppenheimer molecular dynamics and electron propagator theory (EPT). In our work, we utilized a revised version of the Perdew–Burke–Ernzerhof (PBE) exchange-correlation functional, which incorporates empirical corrections for dispersion interactions in line with a recent study of the air–water interface conducted by Ohto et al. [J. Phys. Chem. Lett. 10(17), 4914–4919 (2019)]. Polarization effects induce a significant broadening of the electron binding energy distribution, as predicted by EPT. This broadening can result in a substantial increase in electron affinity, impacting the chemical reactivity of SO2 at the air–water interface, a topic of significant and recent research interest. We discuss the relationship between electron binding energies (EBEs) and the specific connections of SO2 to water. The results indicate that configurations involving an OS⋯H bond tend to yield higher electron affinities compared to complex formation through S⋯OW bonds. Surprisingly, SO2 molecules not bound to water molecules according to a specific criterion may also exhibit higher electron affinities. This feature can be explained by the role played by the polarization field from water molecules. Our best estimate for the HOMO–LUMO (H–L) gap of SO2 at the surface of a water cluster is 11.6 eV. Very similar H–L gaps are predicted for isolated and micro-solvated SO2. Fukui functions for the gas phase, and the micro-solvated SO2–H2O complex supports the view that the LUMO is predominantly localized on the SO2 moiety. [ABSTRACT FROM AUTHOR]

The GW electron–hole interaction kernel, which includes two second-order exchange terms in addition to the first-order direct and exchange terms considered in the conventional GW + Bethe–Salpeter method, is applied to 10 two-molecular systems and six thermally activated delayed fluorescence (TADF) molecules in which inter- and intramolecular charge transfer excitations are expected to occur. The contributions of the two second-order exchange terms are almost zero for intermolecular charge transfer excitations and ∼0.75 eV for intramolecular charge transfer excitations according to our exciton analysis method with exciton wave functions. For TADF molecules, we found that the second-order exchange terms are more significant than the first-order exchange terms, and the contributions—even for local-type and delocalized-type excitations—are not negligibly small. We revealed that the two second-order exchange terms are proportional to the molecular size, the exciton binding energy, and the electron–hole overlap strength for intramolecular charge-transfer excitations. We believe that our findings are indispensable for further considerations of the GW method in the future. [ABSTRACT FROM AUTHOR]

A practical ab initio composite method for modeling x-ray absorption and non-resonant x-ray emission is presented. Vertical K-edge excitation and emission energies are obtained from core-electron binding energies calculated with spin-projected ΔHF/ΔMP and outer-core ionization potentials/electron affinities calculated with electron propagator theory. An assessment of the combined methodologies against experiment is performed for a set of small molecules containing second-row elements. [ABSTRACT FROM AUTHOR]

In the present work, two quasi-molecular compounds each involving one antiproton and one electron ( p ̄) , H e + − p ̄ and H − p ̄ , are investigated. Using completely relativistic calculations within the finite-basis method adapted to systems with axial symmetry, the adiabatic potential curves are constructed by numerically solving the two-center Dirac equation. The binding energies of electron are obtained as a function of the inter-nuclear distance and compared with the corresponding nonrelativistic values and relativistic leading-order corrections calculated in the framework of other approaches. A semantic analysis of antiproton quasi-molecular ions with compounds containing a proton (p) instead of an antiproton is given. The advantages of the A-DKB method are demonstrated. [ABSTRACT FROM AUTHOR]

[Display omitted] Mo 2 C, with an electronic structure closely resembling that of Pt, holds significant promise as a catalyst for nonprecious metal-based electrocatalytic hydrogen evolution reactions (HER). This study presents the design and synthesis of Ni and Co bimetallic-doped Mo 2 C (NiCo-Mo 2 C) tandem nanoreactors, engineered by leveraging the concept of a high-gain transistor cascade amplifier. In NiCo-Mo 2 C material, each monomer layer on Mo 2 C rod functions as an individual electrocatalytic nanoreactor, with the rod supporting a tandem configuration of these units. The combined modulation of Ni and Co at NiCo-Mo 2 C interface increases the electron cloud density around Mo and shifts the d-band center negatively, effectively reducing Mo–H* binding energy. The synergy between NiCo-Mo 2 C (1 0 1) and (0 0 2) crystal planes facilitates both water dissociation and H* desorption from Mo sites. This tandem configuration of multicatalytic units achieves enhanced hydrogen evolution, demonstrated by the low overpotential at 10 mA·cm−2 (η 10) values of 129 mV and 180 mV and Tafel slopes of 84 mV·dec−1 and 85 mV·dec−1 in 1 M KOH and 0.5 M H 2 SO 4 , respectively. Through bimetallic modulation, crystal plane synergy, and tandem structuring, this work advances a novel approach to optimizing HER kinetics, presenting a valuable strategy for developing highly efficient, nonprecious metal-based electrocatalysts. [ABSTRACT FROM AUTHOR]

A series of novel 4-((7-chloroquinolin-4-yl)amino)phenyl arenesulfonates were synthesized via a two-step process and characterized by different spectroscopic technique for structural confirmation. The electronic structure of these derivatives was investigated by Density Functional Theory (DFT), a quantum mechanical method. All the derivatives were evaluated for their biological potency. The antibacterial activity was examined against a panel of bacteria, but they were found to be inactive. Antifungal examination demonstrated that these derivatives exhibited good to potent efficacy against fungal strain Candida albicans. Five derivatives had better MIC values between 125–250 μg/mL among all the synthesized compounds. These derivatives inhibited the formation and development of biofilms and other virulence factors of C. albicans such as adhesion and extracellular secreted proteinases and phospholipases. Furthermore, the result showed that these derivatives have low toxicity against human RBC cells. An in silico docking study showed a good binding energy with Als3 protein (PDB ID: 4LE8) and Sap2 protein (PDB ID: 1EAG) for 4-((7-chloroquinolin-4-yl)amino)phenyl 4-isopropylbenzenesulfonate and 4-((7-chloroquinolin-4-yl)amino)phenyl 4-methoxybenzenesulfonate. Considering the inhibitory effects of these derivatives against C. albicans , they can be used as potential candidates for antifungal development. [ABSTRACT FROM AUTHOR]

This study utilizes first-principles methods to systematically explore the structural, electronic, mechanical, thermal, and bonding properties of K 2 LiXH 6 (X = Al, Ga, In) perovskite hydrides. Calculations of elastic constants, binding energies, and phonon dispersion curves confirm the mechanical, thermodynamic, and dynamic stability of these compounds. Analysis of the Pugh's ratio (B/G) and anisotropy index (A) reveal that these hydrides exhibit anisotropic and brittle characteristics. Electronic property studies reveal that K 2 LiXH 6 (X = Al, Ga, In) hydrides are semiconductors with band gaps of 2.904 eV, 1.451 eV, and 2.227 eV, respectively. Thermal property analysis suggests their suitability for high-temperature environments, while hydrogen storage capacity analysis demonstrates their excellent storage performance and desorption temperatures, with gravimetric hydrogen storage capacities of 5.08 wt%, 3.71 wt%, and 2.92 wt%, respectively. These findings not only enhance our understanding of the properties of these materials, but also establish a theoretical foundation and point the way forward for the development of efficient hydrogen storage materials. [Display omitted] • K 2 LiXH 6 (X = Al, Ga, In) perovskites has been investigated using first-principles. • K 2 LiXH 6 (X = Al, Ga, In) exhibits thermodynamic, mechanical, and dynamical stability. • K 2 LiXH 6 (X = Al, Ga, In) is a medium width indirect band gap semiconductor. • K 2 LiXH 6 (X = Al, Ga, In) has a hydrogen storage capacity of 2.92 wt% to 5.08 wt%. • The desorption temperature is found to be 360.2 K for K 2 LiAlH 6. [ABSTRACT FROM AUTHOR]

To establish the role in future drug development, 2,6-diamino pyridine (2,6-DAP) was investigated experimentally using computational tools. NMR (1H,13C), FTIR, and UV–Vis spectra were analyzed for the titled compound. The molecular structure was optimized via DFT with the "B3LYP method with 6-311++G(d,p)" The optimized parameters of the structure were assessed with the observed bond characteristics. The vibrational frequencies were studied, PED was carried out, and the calculated vibrational frequency obtained was compared with the experimentally obtained FTIR. NMR (1H,13C) was calculated and compared with the experimentally obtained spectra. UV–vis spectra are calculated in the gaseous phase and different mediums of solvents (methanol, DMSO) by employing the PCM solvent model and TD-DFT method, and the estimated value was compared with experimentally measured data. NBO analysis was done to study the donor-acceptor interaction. The extent of electron charge transfer inside the molecular structure was examined using HOMO–LUMO energy values. The study of excitation analysis led to the creation of E.D.D and H.D.D maps in methanol and DMSO. The AIM and ELF analysis was employed to compute the iso-surface projections, ellipticity, and binding energies. The MEP and Fukui functions evaluate the molecule's reactive zones. Hirshfeld research was done to analyze interactions among the molecules in the structure of the crystal, and 3D Hirshfeld tops and 2D fingerprint layouts were developed. The molecular docking procedure was used, followed by a 100 ns MD simulation and computation of binding free energy found to delineate the binding affinity of the molecule toward human carbonic anhydrase II (HCA II). Molecular docking studies with several receptor proteins were also conducted to determine the most effective protein-ligand interactions. Biological assessments like drug-likeness also act upon the compound to verify the molecule's drug-like nature. [ABSTRACT FROM AUTHOR]

Urolithin A, an active precursor derived from the metabolism of ellagitanins in rats and humans, is known for its potential health benefits, including stimulating mitophagy and promoting muscular skeletal function. While experimental studies have demonstrated Urolithin A's potential to enhance cellular health, the detailed molecular interactions through which Urolithin A exerts its effects are not fully elucidated. In this study, we investigated the anti-inflammatory, antioxidation and neuroprotective abilities of Urolithin A in selected targets using molecular docking and molecular dynamics simulation methods. Molecular docking studies revealed the strong affinity for receptors involved in inflammation activities, including human p38 MAP kinase (4DLI) with −10.1 kcal/mol interacting with SER252, LYS249, and ASP294 residues. The binding energy in the 5KIR target was −8.6 kcal/mol, interacting with GLN203 through hydrogen bond, and lastly, 1A9U with an affinity of −6.8 with no hydrogen bond formed with Urolithin A and interacts with van der Waals interactions. In oxidant targets, the influence of Urolithin was observed in 1OG5 with −7.9 kcal/mol interacting with GLN185, PHE447. For the 1M17 target, the binding affinity was −7.7 kcal/mol interacting with THR95 residue and 1ZXM target at −7.4 kcal/mol interacting with TYR36, TYR216, and LEU234 residues. The neuroprotective ability of urolithin A was observed in selected targets for acetylcholinesterase; the binding energy was −9.7 kcal/mol interacting with van der Waals and π interactions; for the 1GQR target, the binding energy was −9.9 kcal/mol interacting with van der Waals and π interactions and for β-amylase (1iyt) the binding energy was −5.5 forming hydrogen bond with SER8, GLN15 residues. Molecular Dynamics simulations at 100 ns of Urolithin A compared with reference 4DLI. The Urolithin A-4DLI complex exhibited greater stability than the reference receptor, as confirmed by RMSD, RMSF, Radius of Gyration, Hydrogen bond, and SASA analyses. [Display omitted] • Neuroprotective, antioxidant and anti-inflammatory properties of Urolithin A. • Mechanism of interaction for urolithin A against aging target determined by computational simulation. • Urolithin A strongly interacted with the P38 kinase receptor among different target. • Dynamic, Stability and Conformational Changes upon Urolithin A Binding to p38 MAP Kinase investigated. [ABSTRACT FROM AUTHOR]

The efficient and stable bifunctional catalytic material Ru+20%Cu@Ti is rapidly constructed on titanium substrate by the sol–gel method, and shows excellent durability with continuous electrolysis for more than 300h, and is stabled up to 64h at an industrial-grade current density of 0.5 A cm−2 in 0.5 M H 2 SO 4 or 5.0 M NaCl. [Display omitted] • Highly efficient Ru-Cu/Ti-based catalysts are prepared via sol–gel method for 2 h; • Ru + 20 %Cu@Ti electrode for CER and OER achieves outstanding catalytic in neutral electrolyte and seawater; • Large area Ru-20 %Cu@Ti (8.0 cm * 15.0 cm) catalysis at 0.5 A cm−2 durable for more than 64h; • This non-precious electrode facilitates a wider range of industrial applications. The development of cost-effective and corrosion-resistant catalytic electrodes for chlorine/oxygen evolution reaction (CER/OER) in large-scale industrial applications is a significant challenge. Herein, the sol–gel method is employed to achieve a uniform coating of ruthenium (Ru) doping copper (Cu) on titanium sheet (Ru + 20 %Cu@Ti), and the highly efficient industrial grade stable Ti dimensional stable anode can be quickly constructed at 723.15 K for 2 h. Cu doping reduces the vacancy formation energy of surface oxygen, promotes additional lattice oxygen vacancy assisted hydrolysis dissociation pathway, improves the selectivity and specific activity of CER at high concentration doping, and reduces the binding energy of OER intermediates (e.g., *OH, *O, and *OOH) at adjacent Ru active sites. The overpotentials require to reach the current density of 10 mA cm−2 for CER and OER were only 365 mV and 232 mV at the conditions of 5.0 M NaCl (pH = 7.0) and 1.0 M KOH + 0.5 M NaCl. More importantly, Ru + 20 %Cu@Ti demonstrates excellent stability, operates continuously for over 340h at industrial current density in neutral and alkaline electrolytes, and its strengthening life reaches 64 h, with ultra-low performance attenuation. Impressively, the designed applied electrode (8.0 cm ✕ 15.0 cm) achieves long-term CER at 0.2–0.3 A cm−2. Further industrial grade evaluation of CER shows that its chlorine extraction polarizability, enhances life and weight loss meet the requirements of industrial applications. [ABSTRACT FROM AUTHOR]

The [3 + 2] cycloaddition (32CA) reactions involving 6-butoxy-5,6-dihydro-4H-1,2-oxazine 2-oxide and dimethyl maleate are examined in this study. Molecular electron density theory (MEDT) is applied at the M06-2X/6-311G(d,p) level, coupled with the D3 dispersion correction. The nitronate 1 species are identified as zwitterionic entities through an analysis of the electron localization function (ELF). This 32CA reaction follows an asynchronous one-step mechanism. Conceptual DFT indices are utilized to classify dimethyl maleate as the electrophilic component and the nitronate as the nucleophilic counterpart. The [3 + 2] cycloaddition processes are predominantly governed by kinetic control, as indicated by activation free energies of − 23.6 and − 11.4 kcal.mol−1 for the exo and endo pathways, respectively, aligning with experimental findings. Despite the nucleophilic and electrophilic character of the reagents, the global electron density transfer at the TSs indicates rather polar 32CA reactions. The formation of a pseudoradical center initiates at carbon atoms C3 and C4. A subsequent docking analysis is conducted on cycloadducts 3 and 4 in relation to the main protease of SARS-CoV-2 (6LU7), alongside the co-crystal ligand. The results of this analysis reveal that cycloadducts 3 exhibit higher binding energy, while cycloadducts 4 display lower binding energy compared to the co-crystal ligand. The results confirm that the presence of isoxazolidine ring increases the affinity of the product 3. [ABSTRACT FROM AUTHOR]

This study explores the nonlinear optical (NLO) properties of hexamine (HMT) doped with transition metals scandium (Sc) and titanium (Ti), exhibiting enhanced NLO responses for advanced photonic devices. Employing ωB97XD functional for optimization and calculations, the study examines geometric parameters, electronic excitation, exciton binding energy (Eb), and vertical ionization energy (VIE) using DFT and TD-DFT. High VIE (3.25 to 4.52 eV) indicates enhanced stability in doped systems. The HOMO-LUMO gap decreases from 10.69 eV in pure HMT to 3.30 to 4.85 eV in the designed systems. These systems exhibit thermodynamic stability with binding energies 3.51 to 4.27 kcal/mol, and Ti-HMT-Ti being the most stable. A two-level approximation method is utilized to determine linear polarizability and nonlinear first and second hyperpolarizability (αstatic, βstatic, γstatic), which exhibits the highest γstatic (6546.63 au) value of Sc-HMT-Sc. Orbital transitions, charge distribution, electrophilicity, and nucleophilicity are examined using TDM, EDDM, and ESP, respectively. PDOS and TDOS provide insights into HOMO-LUMO gap reduction, NCI identifies the weak interactions and broadened and red-shifted UV absorption spectra, all are in the favour of NLO response of designed complexes. So, these materials show exceptional NLO properties and promising for optoelectronic applications. [ABSTRACT FROM AUTHOR]

Hyperexpression of cathepsin B caused by an imbalance of endogenous inhibitors is involved in multiple pathologies, hence making it a key therapeutic target. Protease inhibitors are effective biomolecules that regulate protease activities and are considered potential therapeutic agents in various diseases. Plant protease inhibitors have been reported as an effective complementary alternative drug. A proteinaceous cathepsin B inhibitor (CBI-BP) has been isolated from Musa acuminata Colla (banana) peel with a molecular weight of 27.9 kDa on SDS-PAGE. The purity of the CBI-BP was confirmed on the native- PAGE. The isolated CBI-BP showed an IC 50 value of 8.14 μg and a K i value of 10.59 μg (0.19 μM). Cathepsin B inhibition kinetics indicated that CBI-BP follows a mixed-type of cathepsin B inhibition. Its inhibition activity was also confirmed by reverse zymography. The inhibitor was stable from pH 2.6–10.0 with maximum activity at pH 7.2, temperature 25–100 °C and exhibited thermostability for 60 min at 70 °C. MALDI/TOF/MS analysis of CBI-BP showed 40 % similarity to the GH18 domain-containing protein (A0A4S8JRM9) from Musa balbisiana. Although in-silico docking studies showed binding of A0A4S8JRM9 to cathepsin B affects the binding energy of the substrate to cathepsin B but is not reported for any anti-cathepsin B activity. This suggests that isolated CBI-BP might be a novel protein with anti-cathepsin B activity. Thus the isolated CBI-BP may be further explored as possible anti-cathepsin B drug. [Display omitted] • A 27.9 kDa cathepsin B inhibitor isolated from banana peel (CBI-BP). • A CBI-BP is characterized as mixed type, with a K i value of 10.59 μg. • CBI-BP showed broad pH and temperature stability. • CBI-BP may be suggested as a supplementary phyto-nutraceutical against abnormalities mediated with cathepsin B elevation. [ABSTRACT FROM AUTHOR]

Site-directed mutagenesis was employed to investigate the structure-function relationship of nattokinase (NK) and its effect on the enzymatic activity, thermostability, pH tolerance, and fibrinolytic properties of NK. Specific mutations (T270S, V271I, E262D, and A259T) were introduced within the nk gene, targeting regions predicted to be involved in substrate binding. The NK(E262D) mutant exhibited a significant increase in enzymatic activity (2-fold) and catalytic efficiency (2.2-fold) as assessed by N-Succinyl-Ala-Ala-Pro-Phe p-nitroanilide (Suc-AAPF-pNA) hydrolysis, compared to the wild type. In silico analysis supported these findings, demonstrating lower binding energy for the NK(E262D) mutant, suggesting stronger fibrin affinity. Thermostability assays revealed that NK(E262D) and NK(A259T) displayed exceptional stability, retaining enzyme activity at 60 °C. All mutants exhibited a broader pH tolerance range (pH 5.0–10.0) compared to the wild-type NK. The fibrinolytic activity assay revealed that the E262D mutant possessed the highest fibrinolytic activity (2414 U/mg), surpassing the wild-type. This study reported an NK variant with improved enzymatic activity, thermostability, and fibrinolytic properties. [Display omitted] • Nattokinase mutant generated. • Biochemical characterization of mutant and wild type nattokinase. • Enzyme kinetics carried out. • Clot lysis time determined. • E262D demonstrated enhanced proteolytic activity, fibrinolytic activity and thermostability. [ABSTRACT FROM AUTHOR]

This study aimed to identify chemical compounds derived from Vassobia breviflora methanolic extract using ESI-ToF-MS and their antioxidant potential activity utilizing the following methods: total phenols, DPPH, and ABTS•+. The MTT assay measured cytotoxic activity, while DCFH-DA and nitric oxide assays were employed to determine reactive oxygen species (ROS) and reactive nitrogen species (RNS) levels using African green monkey kidney (VERO) and human keratinocyte (HaCat) cell lines. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were assessed in seven clinical isolates and nine ATCC strains. Biofilm inhibition was tested against four biofilm-forming strains. The antioxidant properties of the methanolic extract were identified as follows: 35.74 mg GAE/g (gallic acid equivalents)/g for total phenols, 10.5 µg/ml for DPPH, and 50.68 µmol trolox/µg for ABTS•+. The mean inhibitory concentration (IC50) values were 622.86 µg/ml (VERO) and 784.33 µg/ml (HaCat). These concentrations did not markedly alter levels of ROS and RNS. Conversely, Bacillus cereus β-hemolytic displayed higher sensitivity to the extract, with MIC of 64 µg/ml and MBC of 128 µg/ml. Enterococcus faecium exhibited the lowest biofilm formation among the tested bacteria. The studied plant exhibited activity against all bacterial strains at concentrations lower than the IC50 VERO and HaCat cells, suggesting potential for future studies. Data present a comprehensive molecular docking analysis against the HlyIIR protein (PDB ID: 2FX0) and determined antimicrobial and endocrine-modulating potentials. Notably, lancifodilactone I and nicandrin B demonstrated the strongest binding affinities, with binding energies of −9.8 kcal/mol and −8.3 kcal/mol, respectively, and demonstrated significant antimicrobial effects against B. cereus. In addition, several compounds showed potential interactions with nuclear receptors, indicating potential endocrine-modulating effects. These findings provide insights into developing target-specific antimicrobial therapies and endocrine-modulating agents. [ABSTRACT FROM AUTHOR]

Background: HCV genotypes are 30–35% polymorphic at the nucleotide level, while subtypes within the same genotype differ by nearly 20%. Although previous studies have shown the immune escape potential of several mutations within the HCV proteins, little is known about the effect of genotype/subtype-specific gene polymorphism on T-cell immunity. Therefore, this study employed several in silico methods to examine the impact of genotype/subtype-specific polymorphisms in Core, NS3, NS5A, and NS5B sequences on T cell epitope processing and HLA-epitope interactions. Methods: For this study, 8,942, 17,700, 14,645, and 3,277 HCV Core, NS3, NS5A, and NS5B sequences, respectively, from eight genotypes and 21 subtypes were retrieved from the Los Alamos HCV Database. Next, the NetCTL tool was employed to predict Cytotoxic T Lymphocyte (CTL) epitopes based on combined proteasomal cleavage, TAP efficacy, and HLA class I receptor binding scores. PEP-FOLD was used to model selected epitopes, followed by peptide-HLA docking using HPEPDOCK. Finally, molecular dynamics simulations were conducted for 200 ns using Desmond software to analyze differences in HLA-epitope (from different HCV genotypes) interaction kinetics and dynamics. Results: A total of 3,410, 8,054, 6,532, and 14,015 CTL epitopes were observed in the HCV Core, NS3, NS5A, and NS5B sequences, respectively. Significant genotype/subtype-specific variations in CTL values and docking scores were observed among NS3, NS5A, and NS5B proteins. In silico results reveal that epitopes from genotype 6b (NS3), 6d/r (NS5B), 6o and 6 k (NS5A) exhibit higher immunogenicity than other genotypes, forming more energetically stable complexes with host receptors. These epitopes, compared to those from the same positions but different genotypes, showed binding energies of −144.24 kcal/mol, −85.30 kcal/mol, and − 43 kcal/mol, respectively. Over a 200 ns MD simulation, GT 6b and 6d/r epitopes displayed up to a 40% stronger binding energy with the HLA receptor. These findings suggest that patients infected with GT 6 may experience enhanced T cell responsiveness and broader immunogenicity. Conclusion: Our study suggests that genotype/subtype-specific polymorphism in HCV may result in altered immune responses by modulating T-cell epitope processing and interaction with HLA receptors. Further experimental studies can be performed to confirm the effect of genotype/subtype-specific polymorphisms on T cell-mediated immune response. [ABSTRACT FROM AUTHOR]

Excitons, bound electron-hole pairs, influence the optical properties in strongly interacting solid-state systems and are typically most stable and pronounced in monolayer materials. Bulk systems with large exciton binding energies, on the other hand, are rare and the mechanisms driving their stability are still relatively unexplored. Here, we report an exceptionally large exciton binding energy in single crystals of the bulk van der Waals antiferromagnet CrSBr. Utilizing state-of-the-art angle-resolved photoemission spectroscopy and self-consistent ab-initio GW calculations, we present direct spectroscopic evidence supporting electronic localization and weak dielectric screening as mechanisms contributing to the amplified exciton binding energy. Furthermore, we report that surface doping enables broad tunability of the band gap offering promise for engineering of the optical and electronic properties. Our results indicate that CrSBr is a promising material for the study of the role of anisotropy in strongly interacting bulk systems and for the development of exciton-based optoelectronics. Chromium sulfur bromide is an air-stable van der Waals magnet, which has a large optical response. Here, Smolenski et al find a large exciton binding energy CrSBr, which they attribute to localization due to the quasi one-dimensional electronic bands. [ABSTRACT FROM AUTHOR]

Revealing the momentum-resolved electronic structure of infinite-layer nickelates is essential for understanding this class of unconventional superconductors but has been hindered by the formidable challenges in improving the sample quality. In this work, we report the angle-resolved photoemission spectroscopy of superconducting La0.8Sr0.2NiO2 films prepared by molecular beam epitaxy and in situ atomic-hydrogen reduction. The measured Fermi topology closely matches theoretical calculations, showing a large Ni dx2-y2-derived Fermi sheet that evolves from hole-like to electron-like along kz and a three-dimensional (3D) electron pocket centered at the Brillouin zone corner. The Ni dx2-y2-derived bands show a mass enhancement (m*/mDFT) of 2 to 3, while the 3D electron band shows negligible band renormalization. Moreover, the Ni dx2-y2-derived states also display a band dispersion anomaly at higher binding energy, reminiscent of the waterfall feature and kinks observed in cuprates. [ABSTRACT FROM AUTHOR]

In this paper, we consider a heavy quarkonium state in a hot QCD medium, namely the ground state of charmonium and bottomonium. The quark–antiquark potential is proposed in the form of a temperature-dependent Cornell potential, and is extended to include a temperature-dependent parameter. Then, for the proposed potential with different parametrizations of the Debye mass, the N-dimensional Schrödinger equation is analytically solved using the biconfluent Heun equation. The obtained energy eigenvalues and wave functions are employed to study the flavor dependence, the effect of dimensionality and the influence of the additional term on the mass and binding energy of 1S state of charmonium and bottomonium at finite temperature. The findings of this research are compared to those from past studies. We concluded that this work provides a simple and consistent description of quarkonium states at finite temperature in a hot QCD medium, highlighting the effect of noncompact extra dimensions and the flavor dependence of the binding energies of heavy quarkonia. [ABSTRACT FROM AUTHOR]

CsPbI 3 quantum dots (QDs) glasses (QDGs) may have excellent photoluminescence (PL) characteristics and stability, which is suitable for wide gamut backlight display. The key problem is to tune the long PL peak to a suitable range of 635–645 nm, and to keep good PL quantum yield (PLQY). We have fabricated CsPbI 3 and Sn-doped CsPbI 3 QDGs in borogermanate glass matrix by melt quenching and thermal treatment. The nanocrystal QDs are confirmed as PL active cubic CsPbI 3 by TEM. To tune the PL peak, small amount of Sn was doped, and two kinds of thermal treatment were used, that were conventional thermal treatment (CTT) and rapid thermal treatment (RTT). For both CTT and RTT, the PL intensity slightly decreases with increasing Sn doping concentration. The peak wavelength can meet the requirement only by RTT. The treatment conditions 540 °C 10 min and Sn doping concentration of 0.3–0.7 % are suitable. Excitation wavelength with strong PL intensity is located at 450 nm, which matches commercial blue LED. PL decay shows average lifetime has strong correlation with the peak wavelength. For the RTT samples of 540 °C/10 min, PL decay lifetime decreases with increasing Sn. The transition wavelengths of transmittance and absorption spectra correlate to the PL peak wavelength. PL peak tuning mechanism is considered as bandgap adjusting effect by B-site CsPb 1-x Sn x I 3 QDs and quantum confinement. By using the Sn-doped CsPbI 3 QDGs with suitable PL peak, color gamut can be improved by 4%–8%. The temperature characteristics of PL spectra have been fitted for CTT and RTT samples with large exciton binding energy of 349–408 meV. Temperature cycle characteristics are excellent. The fabricated Sn-doped CsPbI 3 QDGs are suitable for wide gamut display applications. [ABSTRACT FROM AUTHOR]

TMPRSS4, a transmembrane serine protease type II, is associated with various pathological illnesses. It has been found to activate SARS-CoV-2, enhance viral infection of human small-intestinal enterocytes and is overexpressed in different types of cancers. Therefore, this study aims to disover potential TMPRSS4 inhibitors that have better binding affinity than the approved inhibitors: 2-hydroxydiarylamide and tyroserleutide. Since no 3D-structure is known for TMPRSS4, structural models for the TMPRSS4 serine protease domain were developed. The modeled structures were validated and subjected to molecular dynamics simulations. FDA-approved, clinical/preclinical drugs and natural products were docked to the pocket of TMPRSS4. Moreover, through a systematic analysis, MD simulations and MM-GBSA binding free energy calculations revealed that the best candidates Ergotamine, S55746, NPC478048, Lifirafenib, and NPC77101 are highly stable drug candidates in complex with TMPRSS4, displaying low RMSD and RMSF values with strong binding stability. Among these compounds, Ergotamine showed the most favorable binding energy (-33.73 kcal/mol). Overall, our in silico results revealed that these compounds could act as potent TMPRSS4 inhibitors and need to be validated by future experimental studies. [ABSTRACT FROM AUTHOR]

Three hexaphenylmelamine phosphors substituted with fluorine at meta, ortho, and para positions were synthesized and characterized, showing increasing phosphorescence lifetimes and quantum yields. Crystal analysis and theoretical calculations suggest that the superior RTP of HPM-p-F is attributed to its higher oscillator strength, increased molecular binding energy, and favorable spin–orbit coupling. [ABSTRACT FROM AUTHOR]

Background: The role of cancer-associated pericytes (CAPs) in tumor microenvironment (TME) suggests that they are potential targets for cancer treatment. The mechanism of CAP heterogeneity in esophageal squamous cell carcinoma (ESCC) remains unclear, which has limited the development of treatments for tumors through CAPs. Therefore, a comprehensive understanding of the classification, function, cellular communication and spatial distribution of CAP subpopulations in ESCC is urgently needed. Methods: This study used large-sample single-cell transcriptome sequencing (scRNA-seq) data to investigate pericytes' subpopulation characteristics, functions, upstream and downstream regulation and interactions with other components of the TME in the ESCC, and analyzed prognostically in conjunction with Bulk RNA-seq data. In addition, pericyte subpopulations were validated and their spatial distribution in the ESCC TME was observed by multiplex immunofluorescence. Drug prediction and molecular docking was further used to validate the medicinal value of drug targets. Results: CAPs in the ESCC TME were found to be highly heterogeneous, and we identified six pericyte subtypes: c1_ARHGDIB, c2_BCAM, c3_LUM, c4_SOD2, c5_TYMS, and c6_KRT17, which have commonality in a part of their functions, and each of them has a major function to play, by having different strengths of interaction with different components in the TME. In addition, we found that c4_SOD2 was negatively correlated with prognosis, conversely, c5_TYMS was positively correlated with prognosis. The drug with a better effect on c5_TYMS was docetaxel (binding energy = -8.1, -8.7 kcal/mol); raloxifene may be more effective against c4_SOD2, although raloxifene has a slightly lower binding energy to SOD2 (-6.4 kcal/mol), it has a higher binding energy to PDGFRβ (-8.1 kcal/mol). Conclusion: The present study identified and discovered pericyte subpopulations that were significantly associated with prognosis, which provides new biomarkers for predicting patient prognosis and adds usable targets for immunotherapy, and it is also important for gaining insights into the composition of the TME in ESCC. [ABSTRACT FROM AUTHOR]

Precise binding free-energy predictions for ligands targeting metalloproteins, especially zinc-containing histone deacetylase (HDAC) enzymes, require specialized computational approaches due to the unique interactions at metal-binding sites. This study evaluates a docking algorithm optimized for zinc coordination to determine whether it could accurately differentiate between protonated and deprotonated states of hydroxamic acid ligands, a key functional group in HDAC inhibitors (HDACi). By systematically analyzing both protonation states, we sought to identify which state produces docking poses and binding energy estimates most closely aligned with experimental values. The docking algorithm was applied across HDAC 2, 4, and 8, comparing protonated and deprotonated ligand correlations to experimental data. The results demonstrate that the deprotonated state consistently yielded stronger correlations with experimental data, with R2 values for deprotonated ligands outperforming protonated counterparts in all HDAC targets (average R2 = 0.80 compared to the protonated form where R2 = 0.67). These findings emphasize the significance of proper ligand protonation in molecular docking studies of zinc-binding enzymes, particularly HDACs, and suggest that deprotonation enhances predictive accuracy. The study's methodology provides a robust foundation for improved virtual screening protocols to evaluate large ligand libraries efficiently. This approach supports the streamlined discovery of high-affinity, zinc-binding HDACi, advancing therapeutic exploration of metalloprotein targets. A comprehensive, step-by-step tutorial is provided to facilitate a thorough understanding of the methodology and enable reproducibility of the results. [ABSTRACT FROM AUTHOR]

Brassica napus is a member of the cruciferous family with rich glucosinolate (GSL) content, particularly glucobrassicin (3-indolylmethyl glucosinolate, I3M), that can be metabolized into indole-3-carbinol (I3C), a compound with promising anticancer properties. To unravel the genetic mechanism influencing I3C content in rapeseed seedlings, a comprehensive study was undertaken with a doubled haploid (DH) population. By quantitative trait loci (QTL) mapping, seven QTL that were located on A01, A07, and C04 were identified, with the most significant contribution to phenotypic variation observed on chromosome A07 (11.78%). The genes within the QTL confidence intervals (CIs) include transcription factors (TFs) and glycosyltransferases. After co-expression analysis, GSL-related regulatory network of TFs-targets was constructed and two TFs, BnaA07.ERF019 and BnaA07.NAC92, were identified as possible regulators in GSL biosynthesis. Three IGMT (glucosinolate methyltransferases) genes were found within the CIs that expressed higher in seedlings with more I3C, indicating their roles in I3C synthesis regulation. Molecular docking studies validated the binding capability of I3M to IGMTs, and those within the I3C QTL CIs have the strongest binding energy. These new discoveries offer critical insights into the genetic regulation of I3C content in rapeseed seedlings and establish a foundation for breeding high-I3C rapeseed varieties with potential health-promoting properties. [ABSTRACT FROM AUTHOR]