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B6O7OH62− is a highly polymerized borate anion of three six‐membered rings. Limited research on the B6O7OH62− hydrolysis mechanism under neutral solution conditions exists. Calculations based on density functional theory show that B6O7OH62− undergoes five steps of hydrolysis to form H3BO3 and BOH4−. At the same time, there are a small number of borate ions with different degrees of polymerization during the hydrolysis process, such as triborate, tetraborate, and pentaborate anions. The structure of the borate anion and the coordination environment of the bridging oxygen atoms control the hydrolysis process. Finally, this work explains that in existing experimental studies, the reason for the low B6O7OH62− content in solution environments with low total boron concentrations is that it depolymerizes into other types of borate ions and clarifies the borate species. The conversion relationship provides a basis for identifying the possibility of various borate ions existing in the solution. This work also provides a certain degree of theoretical support for the cause of the "dilution to salt" phenomenon. [ABSTRACT FROM AUTHOR]

Hydrogen storage is indeed fundamental to utilizing H 2 effectively, and porous carbon materials have emerged as highly promising supports for this purpose. γ-Graphyne (γGy) possesses abundant chemical bonds, considerable porosity, and exceptional chemical stability, positioning it as a promising candidate for hydrogen storage and transport applications. In this study, we conducted density functional theory calculations to investigate the potential of Li- and Na-loaded γGy as hydrogen storage materials. Our findings reveal that the hydrogen storage capacity (HSC) of Na-loaded γGy falls significantly short of expectations, whereas Li-loaded γGy demonstrates a notably higher HSC. Subsequently, our calculations indicate that B-doping of γGy does not promote favorable HSC, whereas N-doping exhibits a beneficial effect. Furthermore, we observed that tensile strain favors the hydrogen storage properties of 4Li@γGy and 4Li@N-γGy, while compressive strain enhances the hydrogen storage characteristics of 4Li@B-γGy. Notably, we discovered the capacity to adjust the valence band center of Li (ɛ VB), consequently influencing the hydrogen storage performance of γGy. Our investigation suggests that increased overlap between ɛ VB in Li-loaded graphyne and the effective alignment of H 2 and the supporting structure augments the binding force between Li and H 2 , thereby amplifying the HSC. [Display omitted] • Li-loaded γ-Graphyne stores H 2 via Valence-like interaction. • B- and N-doping can enhance storage capacity of Li-loaded γ-Graphyne. • Valence band center of Li tuned by strain achieve efficient adsorption-desorption. [ABSTRACT FROM AUTHOR]

The need for photosensors and gas sensors arises from their pivotal roles in various technological applications, ensuring enhanced efficiency, safety, and functionality in diverse fields. In this paper, interlinked PbS/Sb2O5 thin film has been synthesized by a magnetron sputtering method. We control the temperature to form the nanocomposite by using their different nucleation temperature during the sulfonation process. A nanostructured PbS/Sb2O5 with cross-linked morphology was synthesized by using this fast and efficient method. This method has also been used to grow a uniform thin film of nanocomposite. The photo-sensing and gas-sensing properties related to the PbS/Sb2O5 compared with those of other nanomaterials have also been investigated. The experimental and theoretical calculations reveal that the PbS/Sb2O5 exhibits extraordinarily superior photo-sensing and gas-sensing properties in terms of providing a pathway for electron transport to the electrode. The attractive highly sensitive photo and gas sensing properties of PbS/Sb2O5 make them applicable for many different kinds of applications. The responsivity and detectivity of PbS/Sb2O5 are 0.28 S/mWcm−2 and 1.68 × 1011 Jones respectively. The sensor response towards NO2 gas was found to be 0.98 at 10 ppb with an limit of detection (LOD) of 0.083 ppb. The PbS/Sb2O5 exhibits high selectivity towards the NO2 gas. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) were used to analyze the geometries, electronic structure, and electronic absorption spectra of a light sensor fabricated by PbS/Sb2O5. The results are very analogous to the experimental results. Both photosensors and gas sensors are indispensable tools that contribute significantly to the evolution of technology and the improvement of various aspects of modern life. [ABSTRACT FROM AUTHOR]

Benzophenone and its derivatives are widely used as UV filters and UV‐ink photoinitiators. The photoinitiating properties of benzophenones depend on their degree of conjugation and delocalization within the molecule. By understanding how conjugation, delocalization, and different substituents affect these properties, benzophenone derivatives can be customized for specific applications. Using quantum mechanical calculations based on B3LYP/6‐311++G(d, p) density functional theory (DFT), chemical reactivity, stability, and photoinitiating capabilities of 4‐(4‐methylphenylthio)benzophenone are analyzed. This includes studying its physical and chemical properties in the gas phase, as well as its excited state electronic transitions, vibrational characteristics, and spectroscopic properties both in gas phase and in various solvents. The DFT‐computed infrared spectra match experimental results. The UV/Visible spectra shows absorption towards longer wavelengths due to extended delocalization of π‐electrons. In different solvents with varying polarity, the absorption spectra exhibit high‐intensity peaks, shift in excitation energy and wavelengths based on the polarity of the solvent. This knowledge allows for the development of novel initiators with customized light absorption, excited state lifetimes, and reaction selectivities, which can enhance processes like UV‐curing, photopolymerization, and other light‐driven reactions. [ABSTRACT FROM AUTHOR]

Hydrogen energy is one of promising non-polluting and renewable energy sources. In this paper, we present a first principal study of hydrogen storage in pure C 60 fullerene cage and Stone-Wales (SW) defective C 60 cages using density functional theory (DFT) with applying both the exchange functional B3LYP and the dispersion correction wb97xd at 6–31+g(d,2p) basis set. In addition, the counterpoise correction is applied, and the basis set superposition error is calculated. The calculations underscore that the hydrogenation binding energy of C 60 cages occurs through an endothermal process for C 60 H in with a hydrogen binding energy of 0.09 eV and through an exothermal process for C 60 H out , C 60 SW 66 H out , and C 60 SW 65 H out , cages with hydrogen binding energies of −2.17 eV, −2.96 eV, and −2.20 eV, respectively. Remarkably, for the first time, the intermediate hydrogen binding energy is found inside C 60 SW 66 H in fullerene, and C 60 SW 65 H in fullerene cages with energies of −0.26 eV and −0.81 eV, respectively. The hydrogen adsorption inside the cavity of C 60 SW 66 fullerene cage is thermodynamically possible below 289.8 K and entire pressure range considered. Our results highlight, for the first time, that the endohedral cavity of C 60 SW 66 is a promising new medium for hydrogen storage due to its binding energies (−0.26 eV) and its hydrogen storage weight percentage (5.3%) that are close to the optimal conditions specified by DOE for commercial use. In addition, this study opens up a new discovery of Stone-Wales defective C 60 fullerene for further endohedral cavity applications. • New insight into endohedral cavity of Stone Wales C 60 SW 66 is reported. • For the first time, a new promising medium for hydrogen storage inside cavity of C 60 SW 66 is proved. • Binding energies of −0.26 eV and hydrogen storage weight percentage up to 5.3% are achieved inside the cavity of C 60 SW 66. • This study opens a new discovery of the SW defective C 60 fullerene for further endohedral cavity applications. [ABSTRACT FROM AUTHOR]

The distribution of stable isotopes in organic compounds within geochemical systems reflects the reactions they undergo, which are often kinetically governed and can be elucidated through quantification based on first principles: employing quantum chemical simulations to derive energy barriers and kinetic isotope effects (KIEs), followed by kinetic calculations using these parameters. In this paper, the distribution of 13C in hydrocarbon gases during the thermal generation and decomposition of ethane and propane has been addressed. The work is based on abundant and systematic isotopic data, including the compound- and position-specific 13C compositions, recent improvements in kinetic networks in hydrocarbon generation, and state-of-the-art quantum chemical methods that can process organic geochemical systems involving solid phases. Density Functional Theory computations validate the carbonium path of hydrocarbon generation and the free-radical path of their decomposition under geological conditions. The first step of each path (alkyl sidechain protonation for generation and hydrogen abstraction for decomposition) is the rate-limiting step and determines the 13C fractionations of gaseous hydrocarbons, with the reaction rate constrained by the concentration or accessibility of the active species (hydrated protons and surface free radicals in the two paths, respectively). Alkyl protonation has normal 13C KIEs, but hydrogen abstraction on the surfaces of solid organic matter has inverse ones (substituting 12C by 13C accelerates the reaction). These inverse KIEs explain three isotopic phenomena in gaseous hydrocarbons in their late thermal evolution: 1) the depletion of 13C in ethane and propane accompanied by their decreased fraction in hydrocarbon gases (isotope "rollover"); 2) the reversed 13C sequence with carbon number (δ13C methane > δ13C ethane > δ13C propane); and 3) the depletion of 13C in the center carbon atoms of residual propane. Isotopic fractionation between gaseous hydrocarbons upon generation is evaluated using the Successive Random Chain-Scission model. The covariation of δ13C in alkanes shows a depletion in CH 4 compared with the values expected from the reciprocal of the carbon numbers, indicating that this deviation may be intrinsic instead of mixing with microbial methane. The comparison of intramolecular 13C fractionation of propane between computational and observed data suggests the contribution of isoprenoids at the beginning of the generation, in addition to isotopic homogenization between the center and end carbon atoms through the ring closure of intermediate cations. The 13C–13C clumping exhibits a weak KIE in both the generation and decomposition of ethane; the clumping is essentially stochastically governed. This work demonstrates how first-principle calculations can provide significant insights into the details of geochemical reactions governing the isotopic distributions. [ABSTRACT FROM AUTHOR]

Vibrational spectroscopy enables critical insight into the structural and dynamic properties of molecules. Presently, the majority of theoretical approaches to spectroscopy employ wavefunction‐based ab initio or density functional methods that rely on the harmonic approximation. This approximation breaks down for large molecules with strongly anharmonic bonds or for molecules with large internuclear separations. An alternative to these methods involves generating molecular anharmonic potential energy surfaces (potentials) and using them to extrapolate the vibrational frequencies. This study examines the efficacy of density functional theory (DFT) and the correlation consistent Composite Approach (ccCA) in generating anharmonic frequencies from potentials of small main group molecules. Vibrational self‐consistent field Theory (VSCF) and post‐VSCF methods were used to calculate the fundamental frequencies of these molecules from their potentials. Functional choice, basis set selection, and mode‐coupling are also examined as factors in influencing accuracy. The absolute deviations for the calculated frequencies using potentials at the ccCA level of theory were lower than the potentials at the DFT level. With DFT resulting in bending modes that are better described than those of ccCA, a multilevel DFT:ccCA approach where DFT potentials are used for single vibrational mode potentials and ccCA is used for vibrational mode‐mode couplings can be utilized for larger polyatomic systems. The frequencies obtained with this multilevel approach using VCIPSI‐PT2 were closer to experimental frequencies than the scaled harmonic frequencies, indicating the success of utilizing post‐VSCF methods to generate more accurate representations of computed infrared spectra. [ABSTRACT FROM AUTHOR]

For a detailed understanding of chemical processes in nature and industry, we need accurate models of chemical reactions in complex environments. While Eyring transition state theory is commonly used for modeling chemical reactions, it is most accurate for small molecules in the gas phase. A wide range of alternative rate theories exist that can better capture reactions involving complex molecules and environmental effects. However, they require that the chemical reaction is sampled by molecular dynamics simulations. This is a formidable challenge since the accessible simulation timescales are many orders of magnitude smaller than typical timescales of chemical reactions. To overcome these limitations, rare event methods involving enhanced molecular dynamics sampling are employed. In this work, thermal isomerization of retinal is studied using tight‐binding density functional theory. Results from transition state theory are compared to those obtained from enhanced sampling. Rates obtained from dynamical reweighting using infrequent metadynamics simulations were in close agreement with those from transition state theory. Meanwhile, rates obtained from application of Kramers' rate equation to a sampled free energy profile along a torsional dihedral reaction coordinate were found to be up to three orders of magnitude higher. This discrepancy raises concerns about applying rate methods to one‐dimensional reaction coordinates in chemical reactions. [ABSTRACT FROM AUTHOR]

Herein, a series of novel ferrocenyl/phenyl/thiophenyl‐azoles was disclosed by vinylic amination of ferrocenyl/phenyl/thiophenyl substituted β‐chloro cinnamaldehydes and acrylonitriles. A highly economical and robust chalcogen‐stabilized iron selenide carbonyl cluster Fe3Se2(CO)9 worked as an efficient catalyst under aerobic conditions. The amination of ferrocenyl/phenyl/thiophenyl substituted β‐chloro‐vinylic Csp2‐Cl with azole derivatives was fully established and fabrication of the Csp2‐N bond was completely supported by various spectral analysis. Moreover, wide range of substrates with functionally different azoles were investigated for the present reaction and good to excellent transformation was recorded. Some of the selected ferrocenated azole derivatives were screened for anti‐cancer activity against the prostate cancer cells (PC‐3) and found to be highly active at low concentration of 5.77 μM with IC50 value. Furthermore, HOMO and LUMO levels and energy gap of some selected compounds were calculated by the density functional theory (DFT). [ABSTRACT FROM AUTHOR]

In women who die from cancer, breast cancer is the most common cause of death. The development of small molecular scaffolds as specific Cyclin-dependent kinase (CDK) inhibitors is a promising strategy in the discovery of anti-breast cancer drugs. Isoindolin-1-ones are heterocyclic compounds with useful therapeutic properties. In this study, a library of 48 isoindolinones has been virtually screened by molecular docking that showed high binding affinity up to − 10.1 kcal/mol and conventional hydrogen bonding interactions with active amino acid residues of CDK7. The molecular dynamics simulation (MDS), fragment molecular orbital (FMO), density functional theory (DFT), and pharmacokinetics studies of the best two docked scored ligands 7 and 14 have been studied. Examining the ligand root mean square deviation and hydrogen bonding occupancy of the 100 ns MDS trajectory, both ligands 7 and 14 showed docked pose stability. FMO calculations displayed that LYS139 and LYS41 are majorly contributing to the binding interactions with ligands 7 and 14 in the docked poses. DFT studies of ligands 7 and 14 showed high values of global softness and low values of global hardness and chemical potential thus displaying chemically reactive soft molecules and this influences their anti-cancer activity. Our hits exhibited superior qualities to known CDK7 inhibitors, according to the comprehensive pharmacokinetic parameters that were predicted. The results indicate that isoindolin-1-one moieties are good candidates for anti-cancer action and could serve as effective CDK7 inhibitors. [ABSTRACT FROM AUTHOR]

Context: The corrosion of mild steel is a significant issue in various industries, prompting the need for effective corrosion inhibitors. This study focuses on understanding the corrosion inhibition properties of organic compounds derived from isoxazole, namely series Iso(a), Iso(b), Iso(c), Iso(d), Iso(e), Iso(f), Iso(g), and Iso(h), which could have implications for materials science and industrial applications. By investigating the influence of different substitutions on these compounds, valuable insights can be gained into designing better corrosion inhibitors for practical use. Methods: Theoretical studies were conducted using density functional theory (DFT) with the B3LYP functional and the 6-31G (d,p) basis set. These calculations enabled the evaluation of various parameters including frontier orbital energies (EHOMO, ELUMO), energy gap (∆E), electronegativity (χ), absolute hardness (η), softness (σ), fraction of transferred electrons (∆N), as well as local properties such as natural atomic populations and Fukui indices. Additionally, molecular dynamics simulations were performed to study the adsorption behavior of the inhibitors on the surface of Fe (110). The simulations were conducted using Materials Studio version 8.0 software package using COMPASS force field to understand the impact of different functional groups on the inhibitors before and after adsorption on the iron surface. [ABSTRACT FROM AUTHOR]

In nature, hydrogen bonding is a common physical occurrence that has a significant impact on the surroundings of anthocyanins. Water molecules will create hydrogen bonds with anthocyanin molecules in various configurations, but the characteristics of these hydrogen bonds will change. Varied hydrogen bonding characteristics have varied impacts on solvent solutions. This research analyzes the differences in hydrogen bonding qualities caused by different methyl structures, as well as the underlying explanations. In this study, the cyanidin and peonidin structures of anthocyanin molecules were calculated in various stable hydrogen bond configurations using the density functional theory B3LYP/6‐31G(d,p), combined with information from the infrared spectroscopy spectrum, atoms in molecules analysis, interaction energy E, and intermolecular hydrogen bond length. The hydrogen bond structure that is the most stable is determined by analyzing it, as well as the effects of replacing the hydroxyl group with a methyl group and any potential underlying causes. Future anthocyanins research can benefit from the precise theoretical reference that this study can offer. [ABSTRACT FROM AUTHOR]

Thiazolin-4-ones and their derivatives represent important heterocyclic scaffolds with various applications in medicinal chemistry. For that reason, the synthesis of two 5-substituted thiazolidin-4-one derivatives was performed. Their structure assignment was conducted by NMR experiments (2D-COSY, 2D-NOESY, 2D-HSQC and 2D-HMBC) and conformational analysis was conducted through Density Functional Theory calculations and 2D-NOESY. Conformational analysis showed that these two molecules adopt exo conformation. Their global minimum structures have two double bonds (C=N, C=C) in Z conformation and the third double (C=N) in E. Our DFT results are in agreement with the 2D-NMR measurements. Furthermore, the reaction isomerization paths were studied via DFT to check the stability of the conformers. Finally, some potential targets were found through the SwissADME platform and docking experiments were performed. Both compounds bind strongly to five macromolecules (triazoloquinazolines, mglur3, Jak3, Danio rerio HDAC6 CD2, acetylcholinesterase) and via SwissADME it was found that these two molecules obey Lipinski's Rule of Five. [ABSTRACT FROM AUTHOR]

Using first principles, the electrical response of carbon nanocones (NC) to the drug benzamide (BZE) was investigated using density functional theory (DFT). The adsorption energies of BZE at the nanocone's bottom (Complex I), side (Complex II), and top (Complex III) are −88.35 kcal/mol, −45.46 kcal/mol and −48.73 kcal/mol. The two other adsorptions, Complexes II and III are physisorption, however, the high value of Eads in the case of Complex I with the drop in bond lengths suggests that Complex I adsorption is chemisorption. The electrical conductivity has risen as a result of the considerable decrease in the nanocone energy gap (from 0.63 eV to 0.61 eV, 0.61 eV and 0.60 eV) caused by the adsorption of BZE. It suggests that the nanocones would be a good fit for the electronic sensors and an appropriate choice for BZE detection. Additionally, the BZE adsorption influences the nanocone's workfunction, which is reduced by approximately 45.19%, 2.8% and 2.05% for complexes I to III. This suggests that the nanocone could be a workfunction-based sensor for the detection of BZE. The increase in binding affinity in complexes reveals that the nanocones will act as a drug delivery carrier. Theoretically, anticipated Raman spectra of BZE and complexes show SERS activity and inactive normal Raman modes are active in the Raman spectrum of complexes. Compounds II and III exhibit weak noncovalent interactions (NCI) and due to the presence of covalent bonding interaction in compound I, significant changes in other bonding and nonbonding electron densities are observed compared to compounds II and III. Adsorption of benzamide on a carbon nanocone Benzamide gives maximum adsorption energy when it is at the bottom of the nanocone Increase in binding affinity in complexes reveals that the nanocones will act as a drug delivery carrier [ABSTRACT FROM AUTHOR]

π–π stacking are omnipresent interactions, crucial in many areas of chemistry, and often studied using quantum chemical methods. Here, we report a simple and computationally efficient method of estimating the binding energies of stacked polycyclic aromatic hydrocarbons based on steered molecular dynamics. This method leverages the force field parameters for accurate calculation. The presented results show good agreement with those obtained through DFT at the ωB97X-D3/cc-pVQZ level of theory. It is demonstrated that this force field-driven SMD method can be applied to other aromatic molecules, allowing insight into the complexity of the stacking interactions and, more importantly, reporting π–π stacking energy values with reasonable precision. [ABSTRACT FROM AUTHOR]

Due to their unique physical and chemical properties, complex nanostructures based on carbon nanotubes and transition metal oxides are considered promising electrode materials for the fabrication of high-performance supercapacitors with a fast charge rate, high power density, and long cycle life. The crucial role in determining their efficiency is played by the properties of the interface in such nanostructures, among them, the type of chemical bonds between their components. The complementary theoretical and experimental methods, including dispersion-corrected density functional theory (DFT-D3) within GGA-PBE approximation, scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman, X-ray photoelectron, and X-ray absorption spectroscopies, were applied in the present work for the comprehensive investigation of surface morphology, structure, and electronic properties in CuOx/MWCNTs and NiOx/MWCNTs. As a result, the type of interfacial interaction and its correlation with electrochemical characteristics were determined. It was found that the presence of both Ni–O–C and Ni–C bonds can increase the contact between NiO and MWCNTs, and, through this, promote electron transfer between NiO and MWCNTs. For NiOx/MWCNTs, better electrochemical characteristics were observed than for CuOx/MWCNTs, in which the interfacial interaction is determined only by bonding through Cu–O–C bonds. The electrochemical properties of CuOx/MWCNTs and NiOx/MWCNTs were studied to demonstrate the effect of interfacial interaction on their efficiency as electrode materials for supercapacitor applications. [ABSTRACT FROM AUTHOR]

The problem of As pollution emission from sludge during combustion has received widespread attention. The impact of flue gas components on the interaction with CaO and As during sludge combustion was analyzed using a series of experimental characterization methods. The strength of the activity of As2O3 on the CaO(001) surface as well as on the CO2/SO2/H2O+CaO(001) surface with different O adsorption sites was revealed by combining with Density Functional Theory (DFT). According to the results, CO2 in the flue gas reacted with CaO in a reversible carbonation reaction, which optimized the pore structure of the solid phase products and promoted the capture of As by CaO. SO2 in the flue gas reacted with CaO in a sulfation reaction reaction to block the pores, which was not conducive to the capture of As by CaO. The presence of moisture led to poor pore structure collapse of the solid phase products as well as the formation of gehlenite, which reduced the enrichment of As by CaO. DFT calculations showed that the adsorption of As2O3 molecules on the CO2+CaO(001) surface was affected by the position of the O active site, and the adsorption energy at the OC1 top site was higher than that on the clean surface, which was favorable for the stable adsorption of As2O3 molecules. The existence of SO2 decreased As2O3 molecules' adsorption energy on the CaO(001) surface, which was unfavorable for the adsorption of As2O3 molecules. There were two main effects of H2O molecules on the adsorption of As2O3 on the CaO(001) surface. One was the H2O molecules weakened the interaction between the As atoms and Osurf atoms, which was unfavorable to the adsorption of As2O3 molecules; the other was the existence of stronger adsorption of O atoms in H2O molecules on As atoms in As2O3 molecules, which made As2O3 molecules adsorbed at the top of OH0 adsorbed with adsorption energies much larger than that of clean surface, and the adsorption was more stable. [ABSTRACT FROM AUTHOR]

The structure, hydrogen bonding, and hydrogen transfer of 1-butyl-3-methylimidazolium hydroxide ([Bmim]OH) aggregations, including dimer and trimer of carbene(α) and covalent(β) conformation, have been investigated using density functional theory B3LYP together with D3 dispersion correction. The geometrical parameters, Gibbs free energy of formation in gas and solution phases were calculated for aggregates of the complex [Bmim]OH conformation. The strengths and binding energies of different types of H-bonds were predicted by quantum theory of atoms-in-molecules descriptors. The results show that O–H···C hydrogen bonds were formed between most hydroxyl protons and the carbon atom of the carbene ring (C2) in [Bmim]OH aggregations. Furthermore, we examine the proton transfer in dimer and trimer conformation of [Bmim]OH, the reaction pathway for proton transfer from hydroxyl of β-conformer to carbene ring was investigated, and the proton transfer process is energetically favorable. [ABSTRACT FROM AUTHOR]

The influence of the crystal synthesis method on the crystallographic structure of caffeine–citric acid cocrystals was analyzed thanks to the synthesis of a new polymorphic form of the cocrystal. In order to compare the new form to the already known forms, the crystal structure of the new cocrystal (C8H10N4O2·C6H8O7) was solved by powder X‐ray diffraction thanks to synchrotron experiments. The structure determination was performed using 'GALLOP', a recently developed hybrid approach based on a local optimization with a particle swarm optimizer, particularly powerful when applied to the structure resolution of materials of pharmaceutical interest, compared to classical Monte‐Carlo simulated annealing. The final structure was obtained through Rietveld refinement, and first‐principles density functional theory (DFT) calculations were used to locate the H atoms. The symmetry is triclinic with the space group P and contains one molecule of caffeine and one molecule of citric acid per asymmetric unit. The crystallographic structure of this cocrystal involves different hydrogen‐bond associations compared to the already known structures. The analysis of these hydrogen bonds indicates that the cocrystal obtained here is less stable than the cocrystals already identified in the literature. This analysis is confirmed by the determination of the melting point of this cocrystal, which is lower than that of the previously known cocrystals. [ABSTRACT FROM AUTHOR]

This study reports the synthesis and crystal structure determination of a novel CrTe3 phase using various experimental and theoretical methods. The average stoichiometry and local phase separation of this quenched high‐pressure phase were characterized by ex situ synchrotron powder X‐ray diffraction and total scattering. Several structural models were obtained using simulated annealing, but all suffered from an imperfect Rietveld refinement, especially at higher diffraction angles. Finally, a novel stoichiometrically correct crystal structure model was proposed on the basis of electron diffraction data and refined against powder diffraction data using the Rietveld method. Scanning electron microscopy–energy‐dispersive X‐ray spectrometry (EDX) measurements verified the targeted 1:3 (Cr:Te) average stoichiometry for the starting compound and for the quenched high‐pressure phase within experimental errors. Scanning transmission electron microscopy (STEM)–EDX was used to examine minute variations of the Cr‐to‐Te ratio at the nanoscale. Precession electron diffraction (PED) experiments were applied for the nanoscale structure analysis of the quenched high‐pressure phase. The proposed monoclinic model from PED experiments provided an improved fit to the X‐ray patterns, especially after introducing atomic anisotropic displacement parameters and partial occupancy of Cr atoms. Atomic resolution STEM and simulations were conducted to identify variations in the Cr‐atom site‐occupancy factor. No significant variations were observed experimentally for several zone axes. The magnetic properties of the novel CrTe3 phase were investigated through temperature‐ and field‐dependent magnetization measurements. In order to understand these properties, auxiliary theoretical investigations have been performed by first‐principles electronic structure calculations and Monte Carlo simulations. The obtained results allow the observed magnetization behavior to be interpreted as the consequence of competition between the applied magnetic field and the Cr–Cr exchange interactions, leading to a decrease of the magnetization towards T = 0 K typical for antiferromagnetic systems, as well as a field‐induced enhanced magnetization around the critical temperature due to the high magnetic susceptibility in this region. [ABSTRACT FROM AUTHOR]

The corrosion inhibition of Thymus leptobotrys Murb essential oil (TLMEO) is evaluated for mild steel (M-S) in 1M HCl solution using electrochemical and surface analysis. Results showed that TLMEO acted as a potential corrosion inhibitor and shows the highest inhibition efficiency of 91.7% at 2g/l concentration. Electrochemical studies suggest that TLMEO acted as a mixed- and interface-type of corrosion inhibitor. The TLMEO inhibits metallic corrosion through an adsorption mechanism that follows Langmuir's adsorption isotherm model. The adsorption mechanism of corrosion inhibition was further supported using SEM–EDX, and surface studies. In addition, the anti-corrosion mechanism of the main TLMEO compounds was studied using computational techniques: Density Functional Theory (DFT) and Molecular Dynamics (MD) simulations. Theoretical results were consistent with the experimental findings that were reported. [ABSTRACT FROM AUTHOR]

Finding cost-effective and sustainable methods for the removal of hydrogen sulfide (H2S), a highly toxic gas released as a byproduct in many industrial activities, is crucial for environmental health. In this study, the adsorption and electronic sensor properties of Ti, V, Cr and Sc doped graphene nanosheets (GN) for H2S molecule have been investigated using Density Functional Theory (DFT) method. The WB97XD method with 6-31G(d,p)/LanL2DZ basis sets have been utilized in DFT calculations. The charge distribution indicates that the charge transfer occurred between metal doped graphenes and H2S. DFT calculations of H2S molecule adsorption on Ti, V, Cr and Sc doped graphenes demonstrate that the ability to adsorb H2S molecule. The obtained adsorption energy (∆E) values vary in the range of -54.4 to -71.0 kJ/mol. Furthermore, the electrical conductivity of the Cr doped graphene nanosheet (Cr-GN) changed due to the change in the HOMO–LUMO gap (∆Eg = 24.8 kJ/mol). This result indicates that the Cr-GN structure is a potential candidate as an electronic sensor for H2S molecule at room temperature. Through methods like DFT, which are cost-effective and highly compatible with experimental results, predicting suitable adsorbents, understanding their properties, and enhancing them are expected to make substantial contributions to the industrial-scale production of these materials in terms of cost and accuracy in the future. [ABSTRACT FROM AUTHOR]

This study conducts a comprehensive investigation into the electronic characteristics and optical behaviour of hetero-ring doped graphene quantum dots (GQDs) using a combination of density functional theory and many-body perturbation methods. The focus is on exploring a novel doping mechanism involving the interplay between the type and positioning of dopant rings, specifically Morpholone, Oxazole, and Thiazole rings. The doping process significantly alters the structural, electronic, and optical properties of the pristine GQD. Structural distortions are observed in the doped nanostructures due to variations in atomic radii and electronegativity among C, O, N, and S atoms. The HOMO-LUMO (H–L) band gap and optical gap exhibit reduction upon doping. Additionally, the absorption spectra of the doped nanostructures shift to lower energy levels compared to the pristine GQD. This finding, coupled with high binding energies and reduced singlet-triplet splitting, provide insights into the photophysical processes within each studied structure, suggesting potential applications. [ABSTRACT FROM AUTHOR]

The pursuit of new materials with tailored properties is essential for advancing technology. This research focuses on GaXF3 (X = Se, Si) fluoroperovskites, utilizing the density functional theory approach. The study begins by assessing structural properties, revealing stable configurations for both compounds. The results from phonon calculations confirm the thermodynamic stability of the compounds. The relationship between elastic constants, confirms their mechanical stability. Elasticity analysis using the IRelast package indicates their resilience, anisotropic characteristics, and mechanical stability. Electronic properties, including band structure, density of states, and electronic band gaps, show that both materials have a metallic nature. Additionally, optical properties, such as dielectric constants, absorption coefficients, and refractive indices, are explored, providing insights into their interactions with light for optoelectronic applications. Optical property calculations for both GaSeF3 and GaSiF3, indicate their potential suitability for use in optoelectronic devices, particularly LEDs, due to their absorption within the UV–Vis range. These results encompass properties such as reflectivity, refractive index, and absorption coefficients, indicating their relevance to potential applications in optoelectronic devices. These findings enhance our understanding of these materials and lay the groundwork for future advancements in advanced materials science. [ABSTRACT FROM AUTHOR]

Pesticides play an important role in conventional agriculture. Yet, their harmful effects on the environment are becoming increasingly apparent. The occurrence of pesticides is hence being monitored worldwide. For fast, easy, yet sensitive identification, surface-enhanced Raman spectroscopy (SERS) is a powerful tool. In this study, a method is introduced that may be amended to in-field detection of pesticides. Gold and silver nanoparticles were synthesized, size-tailored, and characterized. The herbicide paraquat and the fungicide thiram served as model compounds. The preparation yielded reproducible SERS spectra. Using quantum chemical computation, Raman and SERS spectra were calculated and analyzed. The interpretation of vibrational modes in combination with SERS enhancement and attenuation allowed us to identify compound-specific bands. The assignment was interpreted in terms of the orientation of paraquat and thiram on the gold and silver nanoparticle surfaces. Paraquat preferred a co-planar arrangement parallel to the gold nanoparticle surface and a head-on orientation on the silver nanoparticle. For thiram, breaking of the disulfide bond was recognized, such that interaction with the surface occurred via the sulfur atoms. Successful detection of the pesticides after recollection from vegetable leaves demonstrated the method's applicability for pesticide identification. [ABSTRACT FROM AUTHOR]

Density Functional Theory (DFT) suffers from a strong dichotomy between accuracy and consistency. There exists a paucity of a generic linear route to the systematic improvement of computed results. Benchmark studies are often unidimensional and based on molecular/atomic properties that contour on a single Potential Energy Surface. Thus, the DFT functionals so developed and optimized to similar chemical accuracy lack a universal adherence to the unique density distribution for a fixed nuclear arrangement. We have identified this as a major source of inconsistency within the DFT framework and have explored through the cross-correlations between Structure, Energy, and Dipolar Strength. Since Range Separated Hybrid (RSH) functionals are well-known in literature to produce one of the finest molecular structures in both ground and excited states, in this communication, we have utilized CAM-B3LYP, LC- ω HPBE, and ω -B97XD to explore the above cross-correlations on well-studied test subjects comprising of Anthracene, Tetracene, Phenanthrene and Pyrene in all possible combination of these functionals. The combined responses from the functionals have revealed that major inconsistency operating between structure and energy dictates the variations in the dipolar strength and that lower RMSD and higher charge reorganization are the keys to higher dipolar strength. While LC- ω HPBE stands out, CAM-B3LYP and ω B97XD remain comparatively more like each other except in the Adiabatic Energy Difference (AED) trend. [ABSTRACT FROM AUTHOR]

With the aim of studying the electronic and structural properties of metalloporphyrins, we first prepared the 4-acetoxy-3-methoxy benzaldehyde (1) then by reaction this aldehyde with pyrrole the meso-arylporphyrin, namely the meso-tetrakis(4-acetoxy-3-methoxyphenyl)porphyrin (H2TAMPP) (2) was synthesized. We have also prepared a nickel(II) meso-tetra(aryl)porphyrin with the formula [Ni(TAMPP)] (3). Both two porphyrinic compounds 2–3 have been characterized by UV/Vis, fluorescence, 1H and 13C NMR and IR spectroscopies as well as by MALDI and ESI-HRMS mass spectrometry. Density functional Theory (DFT) calculations at the DFT/B3LYP-D3/6–311 G (d, p) level of theory have been carried out to investigate the HOMO–LUMO orbitals of 2–3 and several global reactive parameters of these two compounds such as the chemical potential, the global hardness, the Mulliken electronegativity, the global softness (S) and the global electrophilicity index. The stability and charge delocalization of 2–3 were studied by natural bond orbital (NBO) analysis. On the other hand, our two porphyrinic species 2–3 were theoretically studied for the adsorption of NO2 and H2S gases using the B3LYP/6-31G (d) bases method. Furthermore, H2TAMPP (2) and its corresponding Ni(II) complex (3) were tested as catalysts of the degradation of the methylene blue (MB) and the methyl orange (MO) dyes using an aqueous solution of hydrogen peroxide. [ABSTRACT FROM AUTHOR]

Benzo[d]‐X‐zolyl‐pyridinyl (XO, S, NH) radicals represent a promising class of redox‐active molecules for organic batteries. We present a multistep screening procedure to identify the most promising radical candidates. Experimental investigations and highly correlated wave function‐based calculations are performed to determine benchmark redox potentials. Based on these, the accuracies of different methods (semi‐empirical, density functional theory, wave function‐based), solvent models, dispersion corrections, and basis sets are evaluated. The developed screening procedure consists of three steps: First, a conformer search is performed with CREST. The molecules are selected based on the redox potentials calculated using GFN2‐xTB. Second, HOMO energies calculated with reparametrized B3LYP‐D3(BJ) and the def2‐SVP basis set are used as selection criteria. The final molecules are selected based on the redox potentials calculated from Gibbs energies using BP86‐D3(BJ)/def2‐TZVP. With this multistep screening approach, promising molecules can be suggested for synthesis, and structure–property relationships can be derived. [ABSTRACT FROM AUTHOR]

This review is about anthraquinone dyes. One of the advantages of organic NLOphores materials is the variety of chromophores explored for a wide range of potential applications in optoelectronics and biology. The second and third harmonic generations, as well as hyper‐Rayleigh scattering (HRS), the Z‐scan technique, degenerate four‐wave mixing (DFWM), and density functional theory (DFT), are all covered in this review. The most active sites for establishing enhanced NLO properties were found to be positions 2 and 6 of the anthraquinone core. The structural characteristics of dyes are used to divide them into subcategories. In each section, structures with a higher NLO response are highlighted. Researchers will benefit from this review when designing and synthesizing NLOphores. [ABSTRACT FROM AUTHOR]

High operating temperatures and sluggish kinetics constrain the commercial application of magnesium-based hydrogen storage materials. To overcome these drawbacks, this work investigates heteroatom sulfur as a catalyst to improve the dehydrogenation of MgH 2 using density functional theory (DFT) and experimental validation. Heteroatom sulfur can influence the dehydrogenation of MgH 2 by modulating interfacial carbon-magnesium interactions and substituting surface hydrogen sites. In particular, DFT calculations reveal that sulfur functional groups facilitate charge transfer and significantly reduce the energy barrier of MgH 2 by 0.32 eV–1.59 eV. Substitution of sulfur atoms at surface hydrogen sites of MgH 2 notably improves dehydrogenation by weakening the Mg–H bond and enabling a sulfur-assisted two-step dehydrogenation mechanism. Experimental results further confirm these theoretical findings. The MgH 2 /900C–20SO 2 sample exhibits that the peak dehydrogenation temperature and the onset dehydrogenation temperature were 19.8 °C and 64 °C lower than that of pure MgH 2 , and a significant reduction in activation energy from 134.52 kJ mol−1 to 92.12 kJ mol−1. This research provides a comprehensive understanding of the catalytic effects of heteroatom sulfur on MgH 2 and offers crucial theoretical and practical insights for the development of more efficient magnesium-based hydrogen storage systems. [Display omitted] • The catalytic mechanism of heteroatom sulfur on the dehydrogenation of MgH 2 was investigated. • It was demonstrated that heteroatom sulfur can enhance the dehydrogenation of MgH 2. • Oxidized sulfur functional groups can weaken Mg–H bonds and facilitate charge transfer. • Some sulfur atoms form MgS in situ with Mg, triggering a two-step dehydrogenation. [ABSTRACT FROM AUTHOR]

The research on rechargeable aqueous Zinc(Zn)‐ion batteries has expanded exponentially. However, the performance of Zn anodes during cycling and their commercial application is restricted by severe corrosion and dendritic formation. In this study, a facile approach is presented to address these challenges by introducing minute quantities of Zr(NO3)4 into the 3 m ZnSO4 electrolyte. The Zr(NO3)4 additive facilitates the creation of a protective layer comprising spatial gradient oxidation alloy (GOA) particles. The insulating zirconium‐based materials provide the necessary potential gradient to induce the Zn plate under the covering film. As a proof of concept, the in situ GOA coating anode exhibits exceptional cycling stability for 8000 cycles and an ultralow hysteresis voltage of 41 mV at current density of 5 mA cm−2. Furthermore, Density Functional Theory analyses reveal that the GOA coating anode homogenizes the electric field surrounding the Zn anode surface providing abundant zincophilic sites for Zn nucleation compared to bare Zn plates. This ensures uniform Zn deposition, preventing dendritic growth. In addition, the in situ characterization and computation of Gibbs free energy (ΔGH*) reveal that the GOA coating anode may effectively suppress the hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]

The structure of the spirocyclic product obtained by reacting catechol with 1,1‐dichloro‐2‐(chloromethyl)cyclopropane is shown by NMR and X‐ray analysis to be that of a 2‐methylcyclopropene (MeCP), instead of the previously reported 2‐methylenecyclopropane (MCP) one. The study of the equilibration between the two isomeric forms by experimental and computational means (including both Density Functional Theory – DFT – and Coupled Cluster with single, double, and perturbative triple excitations – CCSD(T) – calculations) revealed that, at variance with most of the alkylidenecyclopropane/alkylcyclopropene systems described to date, for the compounds of the present study the MeCP derivative is more stable by≈ 2.5–3.0 Kcal mol−1 than the MCP one. The extension of the DFT and CCSD(T) study to other spiro‐MCP/MeCP pairs suggests that the origin of the unexpected shift of the equilibrium position can be tracked back to a combination of electronic and ring‐strain effects. These findings lead to re‐think a long‐standing, and substantially undisputed belief in the area of unsaturated cyclopropane derivatives. [ABSTRACT FROM AUTHOR]

Direct decomposition of H 2 S not only generates H 2 but also reduces sulfur (S) emission. Proper catalysts and/or reactant materials are needed to catalyze its dissociation and accommodate the decomposed S in an economical way. Here, by using the density functional theory (DFT) based calculations, we show that Aluminum (Al) can facilitate the dehydrogenation of H 2 S and the formation of H 2. The remaining S adatoms continue to accumulate on Al surface to reach high S coverage (>0.6 monolayer, ML). Then, S atoms react with surface Al atoms to afford a layer of amorphous Al 2 S 3 (a cathode material for Al–S battery) at relatively low temperature (e.g. 773 K), which will transform into crystal phase at higher temperature (e.g. 1073 K). Our research presents a new way to produce H 2 and Al 2 S 3 from H 2 S and Al. [Display omitted] • H 2 S molecules can decompose on all three low-index Al surfaces via two dehydrogenation steps. For the first step, the rank of the energy barriers is Al(110) < Al(111) < Al(100), while for the second step, it changes to Al(100) < Al(111) < Al(110). • As The H 2 S coverage increases, the first H 2 S dehydrogenation barrier becomes slightly higher. • On the S-covered Al(111), the H 2 S dehydrogenation barrier increase with the increasing S coverage. • At high S coverage (5/8 ML), S adatoms react with the surface Al atoms to form Al 2 S 3. A layer of amorphous Al 2 S 3 will be formed at 773 K and will transform into the crystal phase at higher temperature (1073 K). [ABSTRACT FROM AUTHOR]

The corrosion inhibition performance of the corrosion inhibitors is related to their adsorption behavior on the metals' surface, in general, most of researchers focus on the Langmuir adsorption isotherm to deduce physisorption and chemisorption of corrosion inhibitors, however, which experiences a serious argument in recent years. Furthermore, the famous researchers in corrosion field believe that it is wrong to use the Langmuir adsorption isotherm to determine the adsorption behavior of corrosion inhibitors. Simulation methods such as density functional theory (DFT) and molecular dynamics simulation (MD) are treated as effective tools to deeply insight and gain the adsorption behavior of corrosion inhibitors, which can well illustrate the corrosion inhibition mechanism. The quantum chemical parameters obtained from DFT simulation and adsorption energy calculated from MD simulation could well confirm the physisorption or chemisorption states between the corrosion inhibitor and metal surface. Thus, we systematically review the advantages of DFT and MD simulations in analyzing and probing the corrosion inhibition mechanisms of the corrosion inhibitor. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel type of PILs has been fabricated. • PILs integrate the permanent pores of porous solids with the exceptional properties of ILs. • PILs possess high activity and selectivity for the DBT oxidation. • IL moiety serves as an extractant to enrich DBT and creates an electrostatic solvent effect. • UiO-66 moiety serves as a catalysis to handily catalyze the ODS reaction. Developing a highly efficient strategy for the stabilization of the solid-liquid interface is a persistent pursuit for researchers. Herein, porous ionic liquids based on UiO-66 (Zr) porous materials were synthesized and applied to the selective desulfurization catalysis, which integrates the permanent pores of porous solids with the exceptional properties of ionic liquids. Results show that porous ionic liquids possess high activity and selectivity for dibenzothiophene. Experimental analysis and density functional theory calculations revealed that the ionic liquids moiety served as an extractant to enrich dibenzothiophene into the porous ionic liquids phase through the π···π and C H···π interactions. Additionally, the electrostatic solvent effect in the porous ionic liquids contributes to the stabilization solid-liquid interface, which was favorable for UiO-66 moiety to catalytically activate hydrogen peroxide (H 2 O 2) to generate ·OH radicals, and subsequently oxidized dibenzothiophene to the corresponding sulfone. It is hoped that the development of porous ionic liquids could pave a new route to the stabilization of the solid-liquid interface for catalytic oxidation. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H 2 S) gas is a dual menace since it is not only hazardous to human health and the environment, but it is also flammable. Given these crucial considerations, the need for competent gas sensors for H 2 S detection becomes apparent. In this endeavor, an investigation of the gas-sensing prowess inherent in sensors made from assembled nanosheets of ZnO–NiO arranged into intricate flower-like structures. The sensing materials were prepared using a straightforward solvothermal process. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to thoroughly examine the sensor's chemical properties and structural composition. The gas-sensing abilities of the sensing materials were rigorously assessed, which included a close examination of their electrical response to varied concentrations of H 2 S. The efficacy of the sensors may be due to the synergistic interactions between their distinct flower-like design, endowing them with an expansive surface area for optimum gas adsorption, and the significant catalytic impact supplied by the composition of ZnO–NiO. The results show that the ZnO–NiO flower-like sensors have high sensitivity, selectivity, and stability to H 2 S gas. Within the studied range, the response and recovery times were 51.43 s and 38.11 s respectively at 250 °C in 100 ppm H 2 S. This amalgamation of attributes manifests as an enhancement in the sensors' gas-sensing capabilities, highlighting their suitability for such an application. This research complements the explanation offered by first-principles calculations based on Density Functional Theory (DFT) to dive into the fundamentals of this gas-sensing mechanism. [ABSTRACT FROM AUTHOR]

In this paper, a detailed mechanism is discussed for two processes: deNOx and deN2O. An FAU catalyst was used for the reaction with Cu-Fe bimetallic adsorbates represented by a dimer with bridged oxygen. Partial hydration of the metal centres in the dimer was considered. Ab initio calculations based on the density functional theory were used. The electron parameters of the structures obtained were also analysed. Visualisation of the orbitals of selected structures and their interpretations are presented. The presented research allowed a closer look at the mechanisms of processes that are very common in the automotive and chemical industries. Based on theoretical modelling, it was possible to propose the most efficient catalyst that could find potential application in industry–this is the FAU catalyst with a Cu-O-Fe bimetallic dimer with a hydrated copper centre. The essential result of our research is the improvement in the energetics of the reaction mechanism by the presence of an OH group, which will influence the way NO and NH3 molecules react with each other in the deNOx process depending on the industrial conditions of the process. Our theoretical results suggest also how to proceed with the dosage of NO and N2O during the industrial process to increase the desired reaction effect. [ABSTRACT FROM AUTHOR]

This study presents a new 5-methoxy-1H-indole-2-carboxylic acid (MI2CA) polymorph investigated by single-crystal X-ray diffraction, infrared spectroscopy, and density functional theory (ωB97X-D) calculations employing two basis sets (6-31++G(d,p) and aug-cc-pVTZ). The compound crystallizes in the monoclinic system, space group P21/c (a = 4.0305(2) Å, b = 13.0346(6) Å, c = 17.2042(9) Å, β = 91.871(5)°, Z = 4). In the crystalline structure, the formation of cyclic dimers via double hydrogen bonds O−H⋯O between MI2CA molecules was observed. Interactions between the NH groups of the indole rings and the adjacent methoxy groups, as well as C–H⋯O contacts, significantly influence the spatial arrangement of molecules. The results from DFT calculations, including dimeric and trimeric structures, agree well with the experimental structural and spectroscopic data. Analysis of the infrared spectra confirms the conclusions drawn from X-ray diffraction studies and reveals differences between the IR spectra of the newly obtained polymorph and that reported earlier in the literature. This comprehensive study sheds some light on the MI2CA polymorphism and is important for a potential pharmacological applications of this compound. [ABSTRACT FROM AUTHOR]

This study employs density functional theory (DFT) calculations at the B3LYP/6-311+g(d,p) level to investigate the interaction of XH3 gases (X = N, P, As) with the Mn-phthalocyanine molecule (MnPc). Grimme's D3 dispersion correction is applied to consider long-range interactions. The adsorption behavior is explored under the influence of an external static electric field (EF) ranging from −0.514 to 0.514 V/Å. Chemical adsorption of XH3 molecules onto the MnPc molecule is confirmed. The adsorption results in a significant decrease in the energy gap (Eg) of MnPc, indicating the potential alteration of its optical properties. Quantum theory of atoms in molecules (QTAIM) analysis reveals partially covalent bonds between XH3 and MnPc, and the charge density differenc (Δρ) calculations suggest a charge donation-back donation mechanism. The UV-vis spectrum of MnPc experiences a blue shift upon XH3 adsorption, highlighting MnPc's potential as a naked-eye sensor for XH3 molecules. Thermodynamic calculations indicate exothermic interactions, with NH3/MnPc being the most stable complex. The stability of NH3/MnPc decreases with increasing temperature. The direction and magnitude of the applied electric field (EF) play a crucial role in determining the adsorption energy (Eads) for XH3/MnPc complexes. The Eg values decrease with an increasing negative EF, which suggests that the electrical conductivity (σ) and the electrical sensitivity (ΔEg) of the XH3/MnPc complexes are influenced by the magnitude and direction of the applied EF. Overall, this study provides valuable insights into the suggested promising prospects for the utilization of MnPc in sensing applications of XH3 gases. [ABSTRACT FROM AUTHOR]

In this work we present a computational study of alkaline earth oxides (001) surfaces interfaced with water by means of density functional theory (DFT) in conjunction with ab initio molecular dynamics (AIMD) calculations. We studied the nature of MgO, CaO, SrO, and BaO (001) surfaces in contact with water. Results show that water dissociation is promoted as the alkaline earth metal becomes heavier. Similarly, the coordination number of the cation atoms with water molecules follows the same trend, indicating a more favorable interaction. The combined analysis of rumpling and pair distribution functions allows to provide a correspondence between reactivity of atoms on the surface and capability to coordinate water molecules. Except for MgO, the remaining surfaces display strong structural changes upon hydration, a relevant message when modelling hydrated surfaces. We also investigated the effect of the water thickness by adsorbing a water monolayer and bilayer to the surface. The findings of the study and the adopted approach could be of help for future studies of more complex systems or to provide fundamental rationalizations. [ABSTRACT FROM AUTHOR]

The efficient hydrogen-production through the Aluminum-water reaction has become a prominent subject of interest. The impediment encountered in the reaction can be effectively alleviated by Aluminum-based alloy. In this study, density functional theory (DFT) was utilized to explore the mechanism of water decomposition stage on the surface of aluminum and gallium alloy (AGA). Through surface reaction calculations of 12 stable AGA configurations, it was gradually revealed that the optimal alloy ratio was gallium-to-aluminum at 3.5:1. Analysis of the density of states (DOS) indicated that the presence of gallium amplified the activity of surface aluminum. Moreover, frontier orbital theory and charge density maps confirmed that, due to the weak interaction between Ga and ions, the presence of H 2 inhibited Ga passivation, thereby enhancing the reactivity of AGA. This paper provided valuable insights into the surface reaction mechanisms of AGA using DFT, offering theoretical support for hydrogen production processes. • Density functional theory investigated the early stages of AGA-water reaction. • Modeling AGA (Ga proportions 73.8%–81.2%) yields 12 stable configurations. • Ga:Al = 3.5:1 exhibits highest energies for O 2 , H 2 O, and co-adsorption. • Ga enhances AGA's catalytic activity, shown in DOS graphs comparisons. • AGA plays dual roles in surface hydrogen dynamics. [ABSTRACT FROM AUTHOR]

Density Functional Theory is used to unravel the mechanism of the nitrobenzene to aniline reduction, catalyzed by dioxomolybdenum (VI) dichloride. The use of pinacol as an oxoaccepting reagent and the production of only acetone and water as byproducts, signals a novel and environmentally friendly way to add value to the oxygen‐rich biomass‐derived polyols. The reaction proceeds through three consecutive cycles, each one responsible for one of the three reductive steps needed to yield aniline from nitrobenzene, with nitrosobenzene and hydroxylamine as intermediates. Each cycle regenerates the catalyst and releases one water and two acetone molecules. The mechanism involves singlet/triplet state crossings, a crucial feature in polyoxomolibdate catalyzed processes. The role of the Mo‐coordinated water as the provider of the mysterious protons needed to reduce the nitro group, was revealed. The disclosure of this challenging mechanism and its rate limiting step can contribute to the design of more effective Mo(VI) catalysts. [ABSTRACT FROM AUTHOR]

This investigation employed computational methodologies to assess the therapeutic potential of derivatives (1–16) of pyridoxal isonicotinoyl hydrazone (PIH) as potential treatments for tuberculosis. Various computational techniques, including molecular dynamics simulation, molecular docking, density functional theory, and global chemical descriptors, were employed to analyze the interactions between the ligands and target proteins. Docking results indicated that ligands 6, 7, 8, and rifampin exhibited binding affinities of −8.4, −7.4, −9.2, and − 7.2 kcal mol−1, respectively, against mycobacterium tuberculosis enoyl acyl carrier protein reductase (INHA), with ligand 8 demonstrating superior inhibition. Molecular dynamics (MD) simulations were utilized to assess the stability of protein‐ligand interactions. Remarkably, the Root Mean Square Deviation (RMSD) of the INHA‐ligand 8 complex remained minimal, with peak values at.40,.56,.37, and.50 nm at temperatures of 300, 305, 310, and 320 K, respectively. This suggests superior stability compared to the reference drug rifampin and INHA complex, which exhibited an RMSD range of.2 to.8 nm at 300 K. Furthermore, analysis using Frontier Molecular Orbital (FMO) revealed that the Egap value of ligand 8 (4.407 eV) is lower than all the reference drugs except rifampin. This comprehensive theoretical analysis positions ligand 8 as a promising candidate for anti‐tuberculosis drug development, underscoring the need for further exploration through in vitro and in vivo studies. [ABSTRACT FROM AUTHOR]

Direct carbon solid oxide fuel cells (DC-SOFCs) are high-efficiency and clean power generation systems that can directly utilize solid carbon to produce electricity. However, the cell performance is hampered by the sluggish kinetics of the reverse Boudouard reaction at operating temperatures, as dictated by their operational principle. Here, carbon fuels loaded with varying amounts of MgO catalyst were successfully developed to promote the reverse Boudouard reaction and DC-SOFC performance. At 850 °C, the DC-SOFC powered by 5 wt% Mg-loaded activated carbon achieved peak power output of 236 mW cm−2, demonstrating a notable enhancement of 41.3% compared to that of 165 mW cm−2 in pure activated carbon-fueled cell. Furthermore, the single cell discharged stably for a prolonged duration of 41.6 h under 50 mA, achieving a noteworthy fuel utilization of 33.3% at 850 °C. These underscored the substantial contribution of MgO to the enhancement of DC-SOFC performance and efficiency. More importantly, the MgO catalyst displayed excellent stability without agglomeration during the high-temperature operation of the cell. Density functional theory simulation confirmed experimental findings that MgO reduced the energy barrier of carbon gasification reaction, thereby providing sufficient carbon oxide for cell operation. Finally, the reaction paths and internal mechanism of MgO-catalyzed carbon gasification were proposed to offer theoretical backing for the effective conversion of solid carbon fuel and improvement of cell performance. This study offers original perspectives on advancing carbon gasification reaction catalysts to facilitate the stable and highly efficient operation of DC-SOFCs, contributing to reduced carbon emissions and advancing sustainability. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) calculations of hydrogen adsorption on titanium nitride had previously shown that hydrogen may adsorb on both titanium and nitrogen sites with a moderate adsorption energy. Further, the diffusion barrier was also found to be low. These findings may qualify TiN, a versatile multifunctional material with electronic conductivity, as an electrode material for the hydrogen evolution reaction (HER). This was the main impetus of this study, which aims to experimentally and theoretically investigate the electrocatalytic properties of TiN layers that were processed on a Ti substrate using reactive ion sputtering. The properties are discussed, focusing on the role of oxygen defects introduced during the sputtering process on the HER. Based on DFT calculations, it is shown that these oxygen defects alter the electronic environment of the Ti atoms, which entails a low hydrogen adsorption energy in the range of −0.1 eV; this leads to HER performances that match those of Pt-NPs in acidic media. When a few nanometer-thick layers of Pd-NPs are sputtered on top of the TiN layer, the performance is drastically reduced. This is interpreted in terms of oxygen defects being scavenged by the Pd-NPs near the surface, which is thought to reduce the hydrogen adsorption sites. [ABSTRACT FROM AUTHOR]

In this study, we proposed a novel method that integrates density functional theory (DFT) with the finite field method to accurately estimate the polarizability and dielectric constant of polymers. Our approach effectively accounts for the influence of electronic and geometric conformation changed on the dielectric constant. We validated our method using polyethylene (PE) and polytetrafluoroethylene (PTFE) as benchmark materials, and found that it reliably predicted their dielectric constants. Furthermore, we explored the impact of conformation variations in poly(vinylidene fluoride) (PVDF) on its dielectric constant and polarizability. The resulting dielectric constants of α- and γ-PVDF (3.0) showed excellent agreement with crystalline PVDF in experiments. Our findings illuminate the relationship between PVDF's structural properties and its electrical behavior, offering valuable insights for material design and applications. [ABSTRACT FROM AUTHOR]

In this research, the ground (µg) and excited (µe) state dipole moments of metformin hydrochlorides were determined using Lippert-Mataga, Bakhshiev's, Kawski-Chamma-Viallet, and Reichardt models from fluorescence emission and UV-Vis absorption spectra in various solvents. From solvatochromic effects the calculated excited (µe) dipole moment of metformin hydrochloride were, 8.55 D, 8.34 D, 6.08 D, and 6.40 D using the Lippert-Mataga, Bakhshiev's, Kawski-Chamma-Viallet and Reichardt models respectively. The results also indicated that the dipole moment at the ground state is smaller than the excited state. This is due to solvent polarity having a stronger effect on fluorescence emission than absorption spectra. Similarly, from density functional theory, the calculated ground and excited states dipole moments of metformin hydrochloride using (DFT-B3LYP- 3-21+G*(μg = 10.02 D and μe = 11.94 D), DFT-B3LYP- 6-31+G (d, p) (μg = 8.44 D and μe = 10.87 D), and DFT-B3LYP- 6-311+G (d, p) (μg = 8.24 D and μe = 18.74 D)) analyzed by Gaussian 09W. From the optimized geometry of the molecule, the HOMO-LUMO energy band gap of metformin hydrochloride were computed using DFT [DFT-B3LYP- 3-21+G*(5.51 eV), DFT-B3LYP- 6-31+G (d, p) (5.66 eV), and DFT-B3LYP- 6-311+G (d, p) (5.70 eV)] respectively. [ABSTRACT FROM AUTHOR]

XCoP (XTi, Zr, Hf) half Heusler alloys are investigated through density functional theory in stable non‐magnetic phase. The exchange‐correlation functional Generalized Gradient Approximation (GGA) is used to study these alloys. The equilibrium lattice constants and corresponding ground state energies of the studied alloys are calculated in stable γ‐phase. All these three reported alloys exhibit semiconducting behavior with corresponding bandgap values of 1.40, 1.29, and 1.38 eV for TiCoP, ZrCoP, and HfCoP, respectively. The studied alloys are mechanically stable and ductile in nature. The obtained thermoelectric figure of merit for p‐type TiCoP, ZrCoP and HfCoP are 0.5, 0.6, and 0.7 at 1200 K. Similarly, the figure of merit obtained for n‐type TiCoP, ZrCoP, HfCoP are 0.54, 0.37, and 0.31, respectively, at the same temperature. The investigated favorable transport properties of these alloys show that they are the potential candidates for waste heat energy harvesting application. [ABSTRACT FROM AUTHOR]

Phytochemicals are now increasingly exploited as remedial agents for the management of diabetes due to side effects attributable to commercial antidiabetic agents. This study investigated the structural and molecular mechanisms by which betulinic acid exhibits its antidiabetic effect via in vitro and computational techniques. In vitro antidiabetic potential was analysed via on α-amylase, α-glucosidase, pancreatic lipase and α-chymotrypsin inhibitory assays. Its structural and molecular inhibitory mechanisms were investigated using Density Functional Theory (DFT) analysis, molecular docking and molecular dynamics (MD) simulation. Betulinic acid significantly (p < 0.05) inhibited α-amylase, α-glucosidase, pancreatic lipase and α-chymotrypsin enzymes with IC50 of 70.02 μg/mL, 0.27 μg/mL, 1.70 μg/mL and 8.44 μg/mL, respectively. According to DFT studies, betulinic acid possesses similar reaction in gaseous phase and water due to close values observed for highest occupied molecular orbital (HOMO) and lowest occupied molecular orbital (LUMO) and the chemical descriptors. The dipole moment indicates that betulinic acid has high polarity. Molecular electrostatic potential surface revealed the electrophilic and nucleophilic attack-prone atoms of the molecule. Molecular dynamic studies revealed a stable complex between betulinic acid and α-amylase, α-glucosidase, pancreatic lipase and α-chymotrypsin. The study elucidated the potent antidiabetic properties of betulinic acid by revealing its conformational inhibitory mode of action on enzymes involved in the onset of diabetes. [ABSTRACT FROM AUTHOR]

The hydrogenation of carbon monoxide (CO) offers a promising avenue for reducing air pollution and promoting a cleaner environment. Moreover, by using suitable catalysts, CO can be transformed into valuable hydrocarbons. In this study, we elucidate the mechanistic aspects of the catalytic conversion of CO to hydrocarbons on the surface of manganese-doped graphene oxide (Mn-doped GO), where the GO surface includes one OH group next to one Mn adatom. To gain insight into this process, we have employed calculations based on the density functional theory (DFT) to explore both the thermodynamic properties and reaction energy barriers. The Mn adatoms were found to significantly activate the catalyst surface by providing stronger adsorption geometries. Our study concentrated on two mechanisms for CO hydrogenation, resulting in either CH4 production via the reaction sequence CO → HCO → CH2O → CH2OH → CH2 → CH3 → CH4 or CH3OH formation through the CO → HCO → CH2O → CH2OH → CH3OH pathway. The results reveal that both products are likely to be formed on the Mn-doped GO surface on both thermodynamic grounds and considering the reaction energy barriers. Furthermore, the activation energies associated with each stage of the synthesis show that the conversion reactions of CH2 + OH → CH3 + O and CH2O + OH → CH2OH + O with energy barriers of 0.36 and 3.86 eV are the fastest and slowest reactions, respectively. The results also indicate that the reactions: CH2OH + OH → CH2 + O + H2O and CH2OH + OH → CH3OH + O are the most exothermic and endothermic reactions with reaction energies of −0.18 and 1.21 eV, respectively, in the catalytic pathways. [ABSTRACT FROM AUTHOR]