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Salamo‐type ligand H2L was designed and synthesized and reacted with Cu (II) and Zn (II) acetate, respectively, to obtain two binuclear Cu (II) and Zn (II) complexes: [Cu2(L)2]·2CH3OH (1) and [Zn2(L)2] (2) having the same coordination number but distinct geometries. Complex 1 is a Cu (II) complex containing two crystalline ethanol molecules, where two Cu (II) atoms are surrounded by two utterly deprotonated (L)2− parts, forming slightly twisted tetragonal pyramidal configurations of pentacoordinate. In complex 2, two utterly deprotonated (L)2− parts surround two Zn (II) atoms, forming pentadentate twisted triangular bipyramidal configurations. The complexes were elucidated via IR analyses and ultraviolet spectroscopy. Using DFT theoretical calculation, MEPs, IRI, and Hirshfeld surface analysis to investigate further the molecular interactions and reaction sites. Ultimately, the fluorescence characteristics of H2L and its complexes 1 and 2 were discussed. [ABSTRACT FROM AUTHOR]

As a corrosion inhibitor for mild steel in a molar hydrochloric acid medium, we investigated the potential of Eucalyptus globulus essential oil (EuEO). Through electrochemical impedance spectroscopy (EIS), potentiodynamic polarization curves, and theoretical methods, including DFT/B3LYP 6-31G (d, p) and Monte Carlo simulations, the interactions between the EuEO components and the steel surface were analyzed. D-Allose, Betulinaldehyde, and Uvaol were identified as the major active compounds in the GC-MS analysis. The experimental results showed that EuEO reached an inhibitory efficiency as high as 97% at a 1 g/L concentration. The findings suggest that EuEO operates as a mixed-type inhibitor, reducing both cathodic and anodic reactions, as well as building up a protective coating on the steel surface. Simulations also confirmed that EuEO molecules function as electron donors and acceptors, enhancing corrosion resistance. [ABSTRACT FROM AUTHOR]

Exploring new haloplumbate hybrids and understanding the structure‐activity relationships are of great significance for further promoting their applications in the photovoltaic fields. Herein, with the in situ‐formed [Hmd]+ (md = 2‐methyl‐1,3‐diazinane) templates, a new organic–inorganic hybrid iodoplumbate, namely [Hmd]PbI3 (1), is successfully constructed and then structurally characterized using multiple technical approaches. X‐ray crystallography studies show that compound 1 features the typical 1D chain‐like motifs of [Pb2I6]n2n−, generating the 3D supermolecular network by the extensive hydrogen bond interactions. Interestingly, compound 1 exhibits the semiconductive behavior, with an optical band gap of 2.72 eV. More attractively, the title compound has good photoelectric switching performances under the alternating light irradiation, whose photocurrent densities compete well with or surpass those of many metal halide counterparts. Further theoretical analyses reveal that the title compound has a more dispersive band structure (especially the value band) that facilitates the transport of charge carriers, which may be the main origin of its excellent optoelectronic performance. Presented in this paper also bring the studies of Hirshfeld surface, X‐ray photoelectron spectroscopy (XPS) as well as thermogravimetric analysis. [ABSTRACT FROM AUTHOR]

Forty-five "4H, 8H difurazano[3,4-b;3′,4′-e] pyrazine (DFP) based energetic derivatives" were designed, and their heat of formation, stability, detonation performance, and impact sensitivity properties were comprehensively studied using density functional theory. The changes in these properties caused by changes in the type and quantity of substituents were analyzed. The results showed that the density range of DFP based energetic derivatives was 1.62–2.02 g/cm, the detonation velocity range was 7.02–9.18 km/s, and the detonation pressure range was 20.99–38.72 GPa. The introduction of –NH2 and –NHNH2 groups can effectively reduce the chemical reactivity of the compounds, while the introduction of –NHNH2 groups can efficiently improve the heat of formation and detonation performance of the compounds and reduce the sensitivity of the derivatives. Compounds B8 (4H, 8H bis ([1,2,5] oxadiazolo) [3,4-b:3′,4′-e] pyrizine-4,8-diyl nitrate), C8 (8-(trinitromethyl)-4H, 8H bis ([1,2,5] oxadiazolo) [3,4-b:3′,4′-e] pyrizin-4-yl nitrate), E4 (N-(8-hydrazine-4H, 8H bis ([1,2,5] oxadiazolo) [3,4-b:3′,4′-e] pyrizin-4-yl) nitrate, E8 (8-(nitroamino)-4H, 8H bis([1,2,5] oxadiazolo) [3,4-b:3′,4′-e] pyrizin-4-yl nitrate) can be used as candidates for high-energy density materials. [ABSTRACT FROM AUTHOR]

Vibrations generated by railways may undergo amplification or reduction while traversing the foundations, floors, and spans of adjacent structures. This fluctuation in the vibration intensity, identified as a building's coupling loss, is commonly considered in vibration forecasts through the utilization of universal frequency-independent adjustment parameters. This article employs a theoretical analytical approach to investigate the propagation characteristics of Rayleigh waves in elastic foundation soil, as well as the variations at the contact surface of buildings' foundations. Analytical expressions for the coupling loss coefficient are derived to explore the displacement transfer relationship in the soil–structure interaction. To accurately and efficiently analyze the proposed buildings and site, the entire vibration propagation system is decoupled into substructure systems for independent analytical calculations. Theoretical analytical methods are utilized to obtain the displacement transfer functions between the soil and the structures through the refraction and transmission of waves. From a theoretical perspective, a thorough understanding of the interaction between soil and buildings is achieved. The influence of various variables related to railways and foundations on the building responses is analyzed. By comparing with measured data, the correctness of the analytical form of the coupling loss coefficient is validated, filling a gap in the literature due to the lack of analytical research on displacement transfer losses in soil–structure interactions. [ABSTRACT FROM AUTHOR]

The present paper investigates reflexives in Najdi Arabic (NA). We start by examining how the encoding of reflexivity in NA can be attained lexically, morphologically, and syntactically. We also investigate the argument structure of reflexive constructions in NA in accordance with Reinhart and Siloni’s (2005) bundling approach. Finally, possessive reflexives and their cross-linguistic distribution with definiteness marking are examined, providing empirical coverage to this area in NA. [ABSTRACT FROM AUTHOR]

Context: The crystal and molecular structure, electronic properties, optical parameters, and elastic properties of a 1:2 hexanitrohexaazaisowurtzitane (CL-20)/2-mercapto-1-methylimidazole (MMI) cocrystal under 0 ~ 100 GPa hydrostatic pressure were calculated. The results show that the cocrystal CL-20/MMI undergoes three structural transitions at 72 GPa, 95 GPa, and 97 GPa, respectively, and the structural transition occurs in the part of the MMI compound. Structural mutations formed new bonds S1-S2, C2-C7, and N1C5 at 72GPa, 95 GPa, and 97 GPa, respectively. Similarly, the formation of new bonds is confirmed on the basis of an analysis of the changes in lattice constants, cell volumes, and partial densities of states (PDOS) for S1, S2, C2, C7, N1, and C3 at the corresponding pressures. The optical parameters show that the pressure makes the peaks of various optical parameters of CL-20/MMI larger, and the optical activity is enhanced. The optical parameters also confirm the structural mutation of CL-20/MMI under the corresponding pressure. Method: CL-20/MMI was calculated by using the first-principles norm-conservative pseudopotential based on density functional theory (DFT) in the CASTEP software package. For the optimization results, the Broyden–Fletcher–Goldfarb–Shanno (BFGS) method is selected to optimize the geometry of the cocrystal in the range of 0–100 GPa. GGA/PBE (Perdew–Burke–Ernzerhof) was selected to relax the cocrystal CL-20/MMI fully without constraints at atmospheric pressure. The sampling scheme in the Brillouin zone [10] is the Monkhorst–Pack scheme, and the number of k-point grids was 2 × 2 × 2. By contrast, this study will use the LDA method to calculate. [ABSTRACT FROM AUTHOR]

Computational modelling and simulation have made it possible to considerably advance in the exploration of conformational and dynamical features of the desired compound. It not only assists in the interpretation of the experimental result, but also to provide insights about the internal motions of the molecule at the atomic level. In this work, Density Functional Theory calculations are performed to replicate the experimental electronic structure of 2C4H5ClN4.C4H6O4, and its nature is discussed in detail. The B3LYP/6‐311++G(d,p) basis set applied to evaluate the optimal structure characteristics resulted in revealing the corresponding chemical, physical, and biological properties of the molecule. The energy exchange between the contributor and receiver are examined by Natural Bond Orbital analysis. Based on frontier molecular orbitals analysis, the obtained minimum energy gap (0.199 eV) value ensures the stability of the title compound. The molecular electrostatic potential mapping predicts the electrophilic and nucleophilic charge distributions on the molecule. The 3D topology of the crystal packing is analyzed and interpreted via the energy‐framework simulation studies using CystalExplorer software. Through the In‐silico‐ADME calculations, the drug‐likeness and physicochemical properties of the molecule is predicted. Furthermore, the molecular docking studies are used to determine the bioactivity and anti‐diabetic properties of the title compound. [ABSTRACT FROM AUTHOR]

Multi-celled corrugated-plate CFST walls (MC-CFST walls) are innovative composite members for load bearing and energy dissipation. The corrugated steel plates effectively enhance the confinement capacity of the infilled concrete and reduce steel consumption. In this study, the seismic behavior of MC-CFST walls was investigated through experimental, numerical, and theoretical analyses. Eight specimens were designed considering different key parameters, including the width and depth of the corrugated cell, the amplitude of the corrugated steel plate, and the type of boundary columns. These specimens were tested under axial compression and horizontal cyclic loading. The test results indicated that MC-CFST walls exhibited excellent energy dissipation capacity and ductility. Specimens with boundary columns exhibited shear failure modes, while those without boundary columns exhibited flexural failure modes. Increasing the width of the corrugated cell or reducing the effective depth of the composite wall had a significant negative impact on its seismic performance. Subsequently, the finite element (FE) model was established and verified against experimental results. Finally, based on the full-sectional plasticity assumption and the superposition principle, theoretical formulas for predicting the compression-bending and shear capacities of MC-CFST walls were proposed and validated against experimental data. The results showed that both theoretical formulas could effectively and accurately predict the shear resistance of MC-CFST walls, providing valuable references for practical designs. [ABSTRACT FROM AUTHOR]

The thermodynamic analysis of an increasing-pressure endothermic power cycle (IPEPC) integrated with closed-loop geothermal energy extraction (CLGEE) in a geothermal well at a depth from 2 km to 5 km has been carried out in this study. Using CLGEE can avoid some typical problems associated with traditional EGS technology, such as water contamination and seismic-induced risk. Simultaneous optimization has been conducted for the structural parameters of the downhole heat exchanger (DHE), the CO2 mixture working fluid type, and the IPEPC operating parameters. The CO2-R32 mixture has been selected as the optimal working fluid for the IPEPC based on the highest net power output obtained. It has been found that, when the DHE length is 4 km, the thermosiphon effect is capable of compensating for 53.8% of the pump power consumption. As long as the DHE inlet pressure is higher than the critical pressure, a lower DHE inlet pressure results in more power production. The power generation performance of the IPEPC has been compared with that of the organic Rankine cycle (ORC), trans-critical carbon dioxide cycle (t-CO2), and single-flash (SF) systems. The comparison shows that the IPEPC has more net power output than other systems in the case that the DHE length is less than 3 km, along with a DHE outer diameter of 0.155 m. When the DHE outer diameter is increased to 0.22 m, the IPEPC has the highest net power output for the DHE length ranging from 2 km to 5 km. The application scopes obtained in this study for different power generation systems are of engineering-guiding significance for geothermal industries. [ABSTRACT FROM AUTHOR]

Acridines are a class of bioactive agents which exhibit high biological stability and the ability to intercalate with DNA; they have a wide range of applications. Pyridine derivatives have a wide range of biological activities. To enhance the properties of acridine and 2-amino-3-methylpyridine as the active pharmaceutical ingredient (API), 4-nitrobenzoic acid was chosen as a coformer. In the present study, a mixture of acridine and 4-nitrobenzoic acid forms the salt acridinium 4-nitrobenzoate, C13H10N+ ·C7H4NO4- (I), whereas a mixture of 2- amino-3-methylpyridine and 4-nitrobenzoic acid forms the salt 2-amino-3- methylpyridinium 4-nitrobenzoate, C6H9N2 + ·C7H4NO4- (II). In both salts, protonation takes place at the ring N atom. The crystal structure of both salts is predominantly governed by hydrogen-bond interactions. In salt I, C—H...O and N—H...O interactions form an infinite chain in the crystal, whereas in salt II, intermolecular N—H...O interactions form an eight-membered R2 ² (8) ring motif. A theoretical charge–density analysis reveals the charge–density distribution of the inter- and intramolecular interactions of both salts. An in-silico ADME analysis predicts the druglikeness properties of both salts and the results confirm that both salts are potential drug candidates with good bioavailability scores and there is no violation of the Lipinski rules, which supports the druglikeness properties of both salts. However, although both salts exhibit druglike properties, salt I has higher gastrointestinal absorption than salt II and hence it may be considered a potential drug candidate [ABSTRACT FROM AUTHOR]

Azo dye ligand derived from 4,5-diphenyl imidazole and 4,4-diaminodiphenylmethane was synthesized by diazomium coupling reaction. In this reaction an amine (4,4-diaminodiphenylmethane was converted to the diazonium salt and coupled with 4,5-diphenyl imidazole. The bright coloured Cu(II) and Zn(II) complexes with this ligand were synthesized by refluxing the latest with both metals chloride salts. The prepared compounds were characterized by 1H-NMR, 13C-NMR, FTIR, UV-Visible, molar conductivity and atomic absorption. By the infrared data, the coordination between copper and zinc ions and the azo ligand achieved through the nitrogen of the azo group and one of the nitrogen atoms in the imidazole ring. By the molar conductivity test, the nonelectrolytic nature of both complexes was also confirmed. The suggested structure for these complexes is octahedral. Using density functional theory (DFT) some theoretical data was obtained for the synthesized complexes. The obtained data include the highest occupied and the lowest unoccupied molecular orbitals energy (HOMO and LUMO), electron density, thermodynamic functions (ΔG°, ΔS°, ΔH°, ΔE°), ionization potential (IP), electron affinity (EA), electrophilicity(ὠ), electronegativity (En), chemical hardness (η) and dipole moment (µ). According to these studied parameters some properties of the two complexes were explained and discussed. [ABSTRACT FROM AUTHOR]

Our modern study is going to inspect new inclusion phenomena between the 1-butyl-2,3-dimethylimidazolium tetrafluoroborate [Bdmim]BF4 ionic liquid (IL) and the host α-Cyclodextrin (α-CD) by a 1:1 ratio and newly formed inclusion complex was further explored by the 1H-NMR, FT-IR, UV–vis spectroscopy, PXRD, DSC, and SEM analysis. Molecular docking was also performed to investigate the encapsulation of the inclusion complex in which orientation and it have been seen that the IL [Bdmim]BF4 enters into the α-CD cavity with a 1:1 ratio was further established with the help of Job's plot. Furthermore, the antibacterial activity of [Bdmim]BF4 IL and its inclusion complex was verified against some Gram-positive and Gram-negative bacterial strains. [ABSTRACT FROM AUTHOR]

Background: The computational calculations have been employed as a great tool to understand the stabilization of main group species by carbene ligands, which have been recognized as excellent compounds for coordinating highly reactive main-group elements in their zero oxidation state. Objective: The most important results that have been published up to now shown that N-Heterocyclic carbene and Cyclic (Alkyl)(Amino)Carbene ligands can stabilize main group compounds as highly stable complexes. Methods: That led us to further theoretically investigate the possibility of expanding this feature with phosphorus carbenes which have more electron contributing ability. Results: The bonding condition of the E2L2 molecules (where E is group 14 main group elements and L is Carbene ligands) may be understood in depth due to the combination of two ligands with two groups of 14 elements. The combination provides a guideline for synthesizing molecules with novel bonding motifs. Two atoms of group 14 are stabilized by two donor ligands in this bonding picture. In contrast to the E=E bonds seen in nitrogen carbene complexes, all phosphorus carbene complexes exhibit the E=L double bond character notation L=EE=L. L acts as a strong donor ligand in this complex. Conclusions: the thermodynamic calculations and orbital analysis can predict that complexes of L=E−E=L are stable enough to become isolated in a condensed phase for all compounds. [ABSTRACT FROM AUTHOR]

The hydraulic system drives the cutter head mechanism to realize the excavation of large tunnel boring equipment, which puts forward the technical requirements of high pressure and large flow to the pump source. The traditional small displacement axial piston pump uses a planar valve plate. However, under high flow and heavy load conditions, the planar valve plate configuration is prone to uneven wear due to the high-pressure and -velocity (PV) value and pressure shock, which ultimately affects the reliability of the system. A simulation analysis of the load-bearing characteristics of the spherical valve plate mechanism is conducted. The Computational Fluid Dynamics (CFD) method was used to construct flow field models for different valve plate oil film structures to calculate differences in their load-bearing capacities. Additionally, the reasons for variations in load-bearing characteristics based on the curvature radius of the spherical valve plate were analyzed. The simulation results demonstrate that the spherical valve plate exhibits superior leak and load-bearing performance compared to the traditional flat valve plate. Furthermore, the curvature radius of the spherical valve plate directly affects the pulsation characteristics of the piston pump. Smaller curvature radii increase the contact area of the oil film, resulting in greater fluctuation in oil film load-bearing, whereas larger curvature radii lead to increased oil film leakage. Using simulation calculations on heavy-load, high-displacement axial piston pumps, it is determined that the optimal curvature radius for stable load-bearing is 350 mm. [ABSTRACT FROM AUTHOR]

We study the confinement of relativistic spin-one particles in two spatial dimensions by a quantum ring for systems described by the Duffin–Kemmer–Petiau (DKP) equation. The ring-like geometry is realized by introducing a pseudo-scalar funnel-shape potential into the DKP equation, leading to a generalization of the planar DKP oscillator. Having used a ten-dimensional representation of the DKP matrices, the DKP equation is then mapped into two uncoupled subproblems, the first is associated with states of zero spin-projection (natural parity states) and the second is associated with states having a spin-projection number equal to ±1 (unnatural parity states). For both subproblems the exact wave functions of the system are analytically derived and expressed through the generalized Laguerre polynomials. The corresponding energy eigenvalues are explicitly obtained for natural parity states, while in the unnatural parity case an exact energy equation from which they can be determined is derived.

Hydrazine (HD) and mono‐methyl hydrazine (MMH), as the compositions of rocket fuels and corrosion inhibitor, have a significant impact on the atmospheric environment. The effects of them on the reaction between NO2 and H2O were investigated theoretically from mechanism and kinetics, and it is expected that they can promote the hydrolysis of NO2 due to their lower free energy barriers. For the subsequent reaction HNO3+HONO+HD/MMH, acid base complex and zwitterionic structure were produced through isomerization. When one or two water molecules were involved in the subsequent reaction, only zwitterionic structure can be found with the lower free energy barrier, and the products were more stable than those without water molecules. To study the atmospheric behavior of HD/MMH, the structures, thermodynamics, interaction forces and temperature dependence of the clusters, which were consisted with HNO3 and HONO with the base molecules including ammonia, amine and amide, were further calculated, and the results show that the hydrogen bond is the main interaction in the clusters. The global minima remained fixed when the temperature increases from 200 K to 325 K. The forming reactions of the clusters were spontaneous, suggesting that ammonia, amine and amide can promote the nucleation of HNO3 and HONO molecules. [ABSTRACT FROM AUTHOR]

Within the context of fractional calculus, we investigate novel mathematical possibilities. In this context, using the fractional dispersion relations for the fractional wave equation, we explore a class of the generalized fractional wave equation numerically. Some important classes of differential equations in the theory of wave studies are Drinfeld–Sokolov–Wilson and Shallow Water equations. In this effort, the natural transform decomposition technique has been implemented to investigate the explicit result of fractional-order coupled schemes of Drinfeld–Sokolov–Wilson and Shallow Water coupled systems. The proposed method is obtained by coupling the Natural transform with the Adomian decomposition process. The current technique significantly works to find the approximate solution without any discretization or constraining parameter assumptions. The obtained numerical and graphical outcomes by the devised technique are compared with the available exact result to verify the convergence of the method. For mathematical calculations, the Mathematica software package is used. [ABSTRACT FROM AUTHOR]

A novel heterogeneous polymer supported catalyst Cu‐PVPEVB has been developed by complexation of CuI in the matrix of the polymer poly(4‐vinylpyridine‐co‐ethylvinylbenzene). Characterization of the catalyst using different spectroscopic techniques revealed that the copper metal is bound through the pyridine substructure of the polymer. The versatility of the catalyst was established by utilizing it for Chan‐Lam coupling reactions in an eco‐friendly solvent methanol. High yields of C−N cross coupled products are obtained within a short time in presence of K2CO3 and 10 weight % of the catalyst having 13.6 weight % of copper. The catalyst could be recovered after carrying out the reaction by simple filtration and reused. Additionally, among a variety of N‐functionalized products synthesized during this study, an N‐phenyl isatin derivative was found to be promising candidate as a fluorescent probe for detection of the Hg2+ ion in aqueous acetonitrile solution. [ABSTRACT FROM AUTHOR]

The corrosion inhibition performance of a novel corrosion inhibitor, 1-aminobenzotriazole drug (1-ABT), was comprehensively evaluated through a range of experimental and computational techniques. The effectiveness of 1-ABT as a corrosion inhibitor was investigated using weight loss measurements, electrochemical methods, scanning electron microscopy (SEM), Xray photoelectron spectroscopy (XPS), and quantum chemical/molecular dynamics studies. Experimental findings revealed a positive relationship between the inhibition effectiveness of 1-ABT and its concentration, while displaying a negative correlation with temperature. Notably, the highest achieved inhibition efficiency of approximately 98 % was observed at a concentration of 400 ppm. The adsorption behavior of 1-ABT on the metal surface was found to conform to the Langmuir adsorption isotherm, indicating monolayer formation. The thermodynamic analysis further supported the physiochemisorption nature of the adsorption process. XPS analysis and theoretical investigations confirmed the adsorption of 1-ABT molecules onto the steel surface, with the interaction between the N atoms of 1- ABT and the vacant d-orbitals of Fe atoms playing a significant role. SEM examinations provided additional evidence, demonstrating a notable reduction in the corrosion rate in the presence of 1-ABT. These findings contribute to the understanding of the corrosion inhibition mechanisms and highlight the potential of 1-ABT as an effective inhibitor for mitigating corrosion in various applications. [ABSTRACT FROM AUTHOR]

Converting superfluous CO2 into value-added chemicals is regarded as a practical approach for alleviating the global warming problem. Powered by renewable electricity, CO2 reduction reactions (CO2RR) have attracted intense interest owing to their favorable efficiency. Metal catalysts exhibit high catalytic efficiency for CO2 reduction. However, the reaction mechanisms have yet to be investigated. In this study, CO2RR to CH3OH catalyzed by CuAg bimetal is theoretically investigated. The configurations and stability of the catalysts and the reaction pathway are studied. The results unveil the mechanisms of the catalysis process and prove the feasibility of CuAg clusters as efficient CO2RR catalysts, serving as guidance for further experimental exploration. This study provides guidance and a reference for future work in the design of mixed-metal catalysts with high CO2RR performance. [ABSTRACT FROM AUTHOR]

In the face of an escalating global water crisis, countries worldwide grapple with the crippling effects of scarcity, jeopardizing economic progress and hindering societal advancement. Solar energy emerges as a beacon of hope, offering a sustainable and environmentally friendly solution to desalination. Solar distillation technology, harnessing the power of the sun, transforms seawater into freshwater, expanding the availability of this precious resource. Optimizing solar still performance under specific climatic conditions and evaluating different configurations is crucial for practical implementation and widespread adoption of solar energy. In this study, we conducted theoretical investigations on three distinct solar still configurations to evaluate their performance under Baghdad’s climatic conditions. The solar stills analyzed include the passive solar still, the modified solar still coupled with a magnetic field, and the modified solar still coupled with both magnetic and electrical fields. The results proved that the evaporation heat transfer coefficient peaked at 14:00, reaching 25.05 W/m².°C for the convention pyramid solar still (CPSS), 32.33 W/m².°C for the magnetic pyramid solar still (MPSS), and 40.98 W/m².°C for elecro-magnetic pyramid solar still (EMPSS), highlighting their efficiency in converting solar energy to vapor. However, exergy efficiency remained notably lower, at 1.6%, 5.31%, and 7.93% for the three still types, even as energy efficiency reached its maximum of 18.6% at 14:00 with a corresponding peak evaporative heat of 162.4 W/m². [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) is one of the most technologically promising oxides with a broad range of catalytic and photocatalytic activities. Theoretical modeling, especially density functional theory calculations, has been extensively carried out to understand the geometric structure, electronic structure, reactivity, and reaction mechanisms of TiO2 systems, as well as to develop new catalysts with improved performances. This review summarizes the recent theoretical progress on the well‐defined surfaces of TiO2 crystalline, and focuses on the structures, adsorptions, and reactions on the surface and at the interface. The theoretical methods and models, surface defects, surface doping, water splitting and H2 evolution, methanol conversion, CO2 reduction and CO oxidation, SOx and NOx degradation, CH4 conversion, organic pollutant degradation, CH bond activation and CC bond formation, dye sensitization, as well as the applications of TiO2 in some other fields, have been discussed in detail. This article is categorized under:Structure and Mechanism > Reaction Mechanisms and CatalysisStructure and Mechanism > Computational Matmandatory approximaterials ScienceElectronic Structure Theory > Density Functional Theory [ABSTRACT FROM AUTHOR]

Background: The computational calculations have been employed as a great tool to understand the stabilization of main group species by carbene ligands, which have been recognized as excellent compounds for coordinating highly reactive main-group elements in their zero oxidation state. Objective: The most important results that have been published up to now shown that N-Heterocyclic carbene and Cyclic (Alkyl)(Amino)Carbene ligands can stabilize main group compounds as highly stable complexes. Methods: That led us to further theoretically investigate the possibility of expanding this feature with phosphorus carbenes which have more electron contributing ability. Results: The bonding condition of the E2L2 molecules (where E is group 14 main group elements and L is Carbene ligands) may be understood in depth due to the combination of two ligands with two groups of 14 elements. The combination provides a guideline for synthesizing molecules with novel bonding motifs. Two atoms of group 14 are stabilized by two donor ligands in this bonding picture. In contrast to the E=E bonds seen in nitrogen carbene complexes, all phosphorus carbene complexes exhibit the E=L double bond character notation L=EE=L. L acts as a strong donor ligand in this complex. Conclusions: the thermodynamic calculations and orbital analysis can predict that complexes of L=E−E=L are stable enough to become isolated in a condensed phase for all compounds.

As a corrosion inhibitor for mild steel in a molar hydrochloric acid medium, we investigated the potential of Eucalyptus globulus essential oil (EuEO). Through electrochemical impedance spectroscopy (EIS), potentiodynamic polarization curves, and theoretical methods, including DFT/B3LYP 6-31G (d, p) and Monte Carlo simulations, the interactions between the EuEO components and the steel surface were analyzed. D-Allose, Betulinaldehyde, and Uvaol were identified as the major active compounds in the GC-MS analysis. The experimental results showed that EuEO reached an inhibitory efficiency as high as 97% at a 1 g/L concentration. The findings suggest that EuEO operates as a mixed-type inhibitor, reducing both cathodic and anodic reactions, as well as building up a protective coating on the steel surface. Simulations also confirmed that EuEO molecules function as electron donors and acceptors, enhancing corrosion resistance.

This article discusses the design and synthesis of Y-shaped trimers of chiral phase-transfer catalysts for the asymmetric alkylation of amino acid derivatives. The researchers aimed to develop efficient syntheses of unnatural amino acids to meet the growing demand in the global pharmaceutical market for peptide drugs. They designed a series of Y-shaped trimers and evaluated their catalytic performance. The results showed that the length of the linker between the catalyst and a phloroglucinol moiety was crucial in determining the catalytic performance. The Y-shaped trimers also demonstrated high enantioselectivity in producing phenylalanine derivatives. Computational analysis revealed that the dominant product was the R derivative, formed through a nucleophilic attack. The chiral induction was determined by a Coulomb interaction. [Extracted from the article]

Elucidation of protein function is one of the central issues in the field of life sciences. To study the function of proteins not in isolation, but in a cell or its lysate, thus, it is necessary to selectively label the target protein in a mixture. Affinity labeling is one of several widely used methods for selective labeling; however, this method has the disadvantage that the labeling reagent is always activated, albeit weakly. Therefore, fine‐tuning of the reactivity and/or reaction conditions is generally required for successful target‐selective labeling. We previously developed a new affinity labeling reagent with N‐sulfanylethylanilide (SEAlide) as a key reactive unit. It was designed based on the following hypotheses. SEAlide is less reactive and does not label in the absence of a target protein. Upon target binding, amino acid side‐chain functional groups on the target surface convert SEAlide into a thioester form via N–S acyl transfer, allowing the target to be labeled. However, no evidence has been obtained so far to directly prove the hypothesis. In this study, we examine whether amino acid side‐chain functional groups can activate SEAlide from the viewpoint of theoretical chemistry. The theoretical studies show that the activation free energy and enthalpy of the acyl transfer of SEAlide are reduced in the presence of methylammonium, which is a model for the protonated side chain of Lys, and acetate, which is a model for the deprotonated side chain of Asp/Glu. It suggests that Lys and Asp/Glu side chains could potentially stabilize the activation transition states to accelerate the thioester formation. Furthermore, the significant decrease in the activation enthalpy indicates that the contribution of entropy to the transition state is large. This result supports the original hypothesis that the SEAlide‐based labeling reagent is efficiently activated by binding to the target protein. [ABSTRACT FROM AUTHOR]

Three series of energetic nitroimidazoles and polynitrobenzenes derivatives containing different substituents (for instance -NH2, -N3) were designed and have been optimized at the B3LYP-D3/6- 311+G*** level. The effects of multiple substituents on the properties of these energetic materials were analyzed. The electronic structure, energy gap, heat of formation, detonation performance, thermal stability, and surface electrostatic potential of the compounds were systematically studied. As the number of -NH2 substituents increases, the energy of ΔEHOMO-LUMO descends, and the electronic absorption spectrum of the derivatives moves to a low frequency. The substitution of - NH2 on the benzene ring is not conducive to increasing HOF value of energetic materials. Among all mentioned compounds, trinitroimidazole substituted polynitrobenzene displays the most attractive detonation pressure (33 GPa), and with a high density of 1.88 g/cm³, which has exceeded TATB (31.1 GPa, 1.94 g/cm³). [ABSTRACT FROM AUTHOR]

Based on the shell and plate theory, this paper uses the divide-and-combine method (DCM) to derive an analytical out-of-plane compression buckling limit expression of the basic unit of the core layer of a grid beetle elytron plate (GBEP); the accuracy of expression and the mechanism of GBEP unit buckling are investigated through experiments and finite element (FE) simulation. The results show that: (1) the theoretical expression of the out-of-plane compression buckling limit of a GBEP unit obtained by DCM is applicable and is closer to the test results than the classical solution of the out-of-plane compressive buckling of a cylindrical shell and the theoretical result of Flügge. Based on this, a modified expression of the theoretical result of Flügge's compressive buckling limit load is proposed. (2) Given the significant differences between the theoretical values obtained in this paper and the experimental values, the out-of-plane compressive buckling resistance of the GBEP unit and its mechanism are investigated from the viewpoints of structural parameters η (the ratio of the radius of the trabeculae to the width of the element) and deformation process; the synergistic mechanism of the honeycomb-trabeculae structure is also studied. This paper contributes to improving the bionic system derived from the beetle's forewing. [ABSTRACT FROM AUTHOR]

The tetrahedral shape‐persistent molecule 14+, containing four identical pyridyl pyridinium units connected via a sp3 hybridized carbon atom, has been investigated in detail by means of steady‐state and time resolved spectroscopy. Remarkable photophysical properties are observed, particularly in comparison with protonated and methylated analogues (1H48+, 1Me48+), which exhibit substantially shorter excited state lifetimes and lower emission quantum yields. Theoretical studies have rationalized the behavior of the tetrameric molecules relative to the monomers, with DFT and TD‐DFT calculations corroborating steady‐state (absorption and emission) and transient absorption spectra. The behavior of the monomeric compounds (each consisting in one of the four identical subunits of the tetramers, i. e. 2+, 2H2+ and 2Me2+) considerably differs from that of the tetramers, indicating a strong electronic interaction between the subunits in the tetrameric species, likely promoted by the homoconjugation through the connecting sp3 C atom. 2+ is characterized by a peculiar S1‐S2 excited state inversion, whereas the short‐lived emitting S1 state of 2H2+ and 2Me2+ exhibits a partial charge‐transfer character, as substantiated by spectro‐electrochemical studies. Among the six investigated systems, only 14+ is a sizeable luminophore (Φem=0.15), which is related to the peculiar features of its singlet state. [ABSTRACT FROM AUTHOR]

The present study was devoted to the investigation of the effect of NO2 and OH groups on the structure of two imidazopyridines, namely: (E)-N-(7-methyl-2-phenylimidazo[1,2-a]pyridin-3-yl)-1-(4-nitrophenyl)methanimine (Imid1) and (E)-4-(((7-methyl-2-phenylimidazo[1,2-a]pyridin-3-yl)imino)methyl)phenol (Imid2) on the corrosion inhibition efficiency of steel in an acidic medium, to remediate mild steel in hydrochloric acid. The evaluation of this activity was revealed using several experimental techniques such as weight loss measurements (WL), potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS), UV–visible spectroscopy study, surface characterization by SEM, as well as the impact of temperature and concentration on the inhibition efficiency for two inhibitors. The results obtained from these techniques show that the inhibition efficiency is reduced by the effect of the nitro electron-withdrawing group (NO2) in the Imid1 molecule, but increased by the presence of the donor group (-OH) in the Imid2 molecule. The comparison of the results obtained by UV–visible spectroscopy of the inhibited and uninhibited electrolyte provided evidence for the formation of an Fe-ligand complex of two imidazopyridine molecules in 1 M HCl. Surface morphological studies by SEM revealed a uniform surface in the presence of Imid1-2, in contrast to a destroyed surface in the absence of the inhibitors. Finally, the results of DFT and MDS simulations are in good agreement with the experimental data and showed that the obtained order of the inhibition efficiency is always respected (Imid2 > Imid1). [ABSTRACT FROM AUTHOR]

As a cost-effective production, steel reinforced thermoplastic pipes (S-RTPs) are employed in many industrial fields, such as the marine and petrochemical industries. The design, manufacture, and mechanical properties of S-RTPs are more challenging than those of traditional pipes because of their complicated behaviors and damage mechanisms. A comprehensive review of the design, manufacture, and mechanical behavior of S-RTPs is presented to understand the predictive capabilities, efficiency, and drawbacks of S-RTPs. The limitations of the existing investigations of S-RTPs and the guidance on future research to improve the analysis and design of S-RTPs are also reviewed, discussed, and provided. This article is the first systematic review to consolidate the understanding of the mechanical performance and existing problems related to steel reinforced plastic pipes (S-RTPs). An S-RTP is a cost-effective production, and it has been employed in many industrial fields, such as the marine and petrochemical industries. The design, manufacture, and understanding of mechanical properties of S-RTPs are quite complicated, and they are more challenging than those of traditional pipes like carbon steel pipes, due to their complex behaviors and failure process. However, there has been no review to consolidate the understanding of the behavior and problems related to S-RTPs to the best of our knowledge. This paper reviews existing work in design, manufacture, mechanical properties, and some potential nondestructive testing techniques of S-RTPs to understand the predictive capabilities, efficiency, and drawbacks of S-RTPs. The limitations of the existing investigations of S-RTPs and the guidance on future research to improve the analysis and design of S-RTPs are also reviewed, discussed, and provided. People including scientists, engineers, workers, students, and potential purchasers can get the content of interest about different kinds of S-RTPs from this paper. [ABSTRACT FROM AUTHOR]

The main objective in this article was to identify the links between classical theories on motivation and postulates on the nature and workings of erotic desire, capturing these links in a model of the motivational processing of desire. The paper reviews the most relevant motivation theories identifying their links to the nature of erotic desire, relating the main variables of these motivation theories to the concept of desire, identifying the similarities between the elements of these constructs. The outcome was a theoretical model of the motivational processing of sexual desire that also includes processes for regulating desire in which a highlight is the interaction between external and internal factors in its development. We understand that these implications underpin the need to adopt a motivational and affective approach to erotic desire, as a process that can be self-regulated. This approach stress the need to continue analyzing the affective experience and the motivational process encapsulated in desire in order to increase our understanding of its activation and development. [ABSTRACT FROM AUTHOR]

It is well known that the guanidinium group in Arginine plays an important role in noncovalent interactions. However, its role is not well documented since the selection of its global minimum structure is still controversial. The main difficulties on obtaining accurate results lie on: neutral Arginine can occur in 3 forms, two of which are canonical and one is zwitterion; each form has degenerate enantiomers D- and L-; its numerous degrees of freedom make it challenging to perform a thorough study; the short-range interactions require higher levels of theory to correctly describe them. Thus, we have performed a meticulous global minimum search. We performed optimizations of the systems at the PBE0 / Def2TZVP level of theory and single point calculations at the DLPNO-CCSD(T)/Def2TZVP level with zero-point corrections at PBE0/Def2TZVP. We also analyzed Thermal Populations and IR Spectra of the systems to fully understand Arginine's behavior. The results show the energy minima structures strongly rely on its internal nitrogen-rich groups. [ABSTRACT FROM AUTHOR]

Tetrazole compounds are a category of energetic materials with great potential. Their stability is inherently related to their aromatics. On the basis of research in DFT at b3lyp/6–311** level on three compounds interested, viz. 5-amino-1 H-tetrazole, 5-carboxyl-1 H-tetrazole, and 2-methyl-5-carboxyl-tetrazole, their aromatic characters are extensively analyzed by virtue of different estimation method. Analyses show that these methods, Nucleus-independent Chemical Shift, iso-chemical shielding surface, adaptive natural density partitioning, π-electrons density, and localized orbital locator of π-electron density are efficient for substituted-tetrazole ring aromaticity estimation. Conclusion denotes that both substituent and substituted position can significantly affect the aromaticity of tetrazole ring of tetrazole compound. Among these given substituents, electro-withdrawing group -COOH significantly increases the aromaticity of the tetrazole rings due to the withdrawing to π-electrons thereof but electro-donating group -NH2 weakens the one of the tetrazole rings due to the donating to π-electrons thereof. But for 2-methyl-5-carboxyl-tetrazole, the aromaticity increasing of -COOH imposed on π-electrons of tetrazole ring thereof is partially balanced by the existence of the electron-donating group -CH3 at asymmetric meta-position of tetrazole ring. Consequently, the aromaticity order is 5-Carboxyl-1 H-tetrazole > 2-methyl-5-Carboxyl-tetrazole > 5-amino-1 H-tetrazole. [ABSTRACT FROM AUTHOR]

The green synthesis of 4,5-diphenyl-1H-imidazole derivatives was studied experimentally and theoretically through a one-pot, three-component reaction of diverse aldehydes, ammonium acetate, and benzil using Fe3O4@C@PrNHSO3H nanoparticles under solvent-free conditions. The core-shell magnetic nanoparticles of Fe3O4@C@PrNHSO3H were introduced as an effective, environmentally friendly, and magnetically removable catalyst in the reaction. The recovered catalyst could be used eight times with admirable catalytic activity. Before entering the laboratory, the synthesis of imidazoles was studied from a computational point of view to find the most plausible mechanism and select the appropriate raw materials. Three probable mechanistic paths were considered. Density functional theory (DFT) calculations confirmed the following mechanism: (1) reaction of benzil and ammonia to form iminoethanone, (2) reaction of aldehyde and ammonia to form imin, (3) reaction of imin with iminoethanone and ring formation, and (4) rearrangement to produce 4,5-triphenyl-1H-imidazole. The results were affirmed by the frontier molecular orbitals, natural bond orbital analyses, and molecular electrostatic potential calculations. The green synthesis of 4,5-diphenyl-1H-imidazole derivatives was studied experimentally and theoretically using Fe3O4@C@PrNHSO3H nanoparticles (NPs). Three proposal mechanisms were considered using M062X/6-311++G(d,p) to achieve the most plausible mechanism, The proposed mechanism was verified by the frontier molecular orbitals, natural bond orbital analyses, and molecular electrostatic potential calculations. The Fe3O4@C@PrNHSO3H NPs were introduced as an effective, eco-friendly and magnetically recoverable catalyst in the one-step synthesis of imidazoles. The recovered catalyst could be used eight times with admirable catalytic activity. [ABSTRACT FROM AUTHOR]

We consider the Duffin–Kemmer–Petiau (DKP) oscillator for spin-zero bosons, coupled to a pseudoscalar Coulomb potential, in a (3+1)-dimensional noncommutative space–time characterized by κ-deformation. We use the method of Dirac derivatives to build the κ-deformed DKP equation. We work out the solutions of the generalized oscillator so obtained using a perturbation method: This allowed to examine first-order effects of the non-commutativity on its eigenenergies and eigenfunctions. Notably, we find that, due to the deformation, the energy levels of s-states become discontinuous at a certain critical value of the coupling constant of the Coulomb term. We also note an asymmetry between particle and antiparticle energies revealing the breaking of the charge-conjugation symmetry for deformed DKP equation. In addition, we discuss the κ-deformed DKP oscillator as a particular case of the considered model.

The Extended Uncertainty Principle (EUP) is a gravitational correction to quantum mechanics that extends and modifies Heisenberg’s uncertainty principle. Particularly, it suggests the existence of a minimum measurable momentum scale, often referred to as the Minimal Momentum (MM), a quantity which is expected to influence the properties of all quantum mechanical systems. In this paper we investigate the effects of the EUP on the quantum features of the Two-Dimensional (2D) Duffin-Kemmer-Petiau Oscillator (DKPO) for spin-one particles subject to an external Homogeneous Magnetic Field (HMF). Using the position representation, we solve the corresponding problem and we obtain the exact wave functions and eigenenergies of the system, then we analyze how they are affected by the MM. We also examine the special case of a spin-one particle moving in a plane under a perpendicular HMF.

In this work, α-Ag2WO4 particles with different cross-sections were obtained using the co-precipitation method at different synthesis temperatures. The samples were characterized by X-ray diffraction (XRD), field-scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The antimicrobial activity was analyzed using the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) methods against the Escherichia coli and Salmonella spp. gram-negative bacteria. The antimicrobial tests against Escherichia coli and Salmonella spp. indicated that concentrations of 2.5–5 mg/mL and 5 mg/mL completely inhibit its growth, respectively. The antimicrobial activity was analyzed employing band-edge positions for ROS generations and the superficial distribution of Ag+ species that contribute to antimicrobial activity. Quantum-chemical calculations were used at the DFT level to investigate the surface-dependent reactivity of α-Ag2WO4, and we demonstrated how the antimicrobial properties could be tailored by the geometry and electronic structure of the exposed surfaces, providing guidelines for the morphology design.

Vibrations generated by railways may undergo amplification or reduction while traversing the foundations, floors, and spans of adjacent structures. This fluctuation in the vibration intensity, identified as a building’s coupling loss, is commonly considered in vibration forecasts through the utilization of universal frequency-independent adjustment parameters. This article employs a theoretical analytical approach to investigate the propagation characteristics of Rayleigh waves in elastic foundation soil, as well as the variations at the contact surface of buildings’ foundations. Analytical expressions for the coupling loss coefficient are derived to explore the displacement transfer relationship in the soil–structure interaction. To accurately and efficiently analyze the proposed buildings and site, the entire vibration propagation system is decoupled into substructure systems for independent analytical calculations. Theoretical analytical methods are utilized to obtain the displacement transfer functions between the soil and the structures through the refraction and transmission of waves. From a theoretical perspective, a thorough understanding of the interaction between soil and buildings is achieved. The influence of various variables related to railways and foundations on the building responses is analyzed. By comparing with measured data, the correctness of the analytical form of the coupling loss coefficient is validated, filling a gap in the literature due to the lack of analytical research on displacement transfer losses in soil–structure interactions.

The hydraulic system drives the cutter head mechanism to realize the excavation of large tunnel boring equipment, which puts forward the technical requirements of high pressure and large flow to the pump source. The traditional small displacement axial piston pump uses a planar valve plate. However, under high flow and heavy load conditions, the planar valve plate configuration is prone to uneven wear due to the high-pressure and -velocity (PV) value and pressure shock, which ultimately affects the reliability of the system. A simulation analysis of the load-bearing characteristics of the spherical valve plate mechanism is conducted. The Computational Fluid Dynamics (CFD) method was used to construct flow field models for different valve plate oil film structures to calculate differences in their load-bearing capacities. Additionally, the reasons for variations in load-bearing characteristics based on the curvature radius of the spherical valve plate were analyzed. The simulation results demonstrate that the spherical valve plate exhibits superior leak and load-bearing performance compared to the traditional flat valve plate. Furthermore, the curvature radius of the spherical valve plate directly affects the pulsation characteristics of the piston pump. Smaller curvature radii increase the contact area of the oil film, resulting in greater fluctuation in oil film load-bearing, whereas larger curvature radii lead to increased oil film leakage. Using simulation calculations on heavy-load, high-displacement axial piston pumps, it is determined that the optimal curvature radius for stable load-bearing is 350 mm.

The thermodynamic analysis of an increasing-pressure endothermic power cycle (IPEPC) integrated with closed-loop geothermal energy extraction (CLGEE) in a geothermal well at a depth from 2 km to 5 km has been carried out in this study. Using CLGEE can avoid some typical problems associated with traditional EGS technology, such as water contamination and seismic-induced risk. Simultaneous optimization has been conducted for the structural parameters of the downhole heat exchanger (DHE), the CO2 mixture working fluid type, and the IPEPC operating parameters. The CO2-R32 mixture has been selected as the optimal working fluid for the IPEPC based on the highest net power output obtained. It has been found that, when the DHE length is 4 km, the thermosiphon effect is capable of compensating for 53.8% of the pump power consumption. As long as the DHE inlet pressure is higher than the critical pressure, a lower DHE inlet pressure results in more power production. The power generation performance of the IPEPC has been compared with that of the organic Rankine cycle (ORC), trans-critical carbon dioxide cycle (t-CO2), and single-flash (SF) systems. The comparison shows that the IPEPC has more net power output than other systems in the case that the DHE length is less than 3 km, along with a DHE outer diameter of 0.155 m. When the DHE outer diameter is increased to 0.22 m, the IPEPC has the highest net power output for the DHE length ranging from 2 km to 5 km. The application scopes obtained in this study for different power generation systems are of engineering-guiding significance for geothermal industries.

Graphyne is of great interest to researchers due to its unique electronic and mechanical properties, which make it a potentially valuable material for a wide range of applications. The importance of graphyne lies in its potential to enable new technologies and applications in a variety of fields, from electronics to materials science. In this paper, the density functional theory (DFT) calculation was used to investigate CO2 and N2 adsorption on pristine and oxidized γ-graphyne in both two horizontal and vertical directions at hollow and bridge sites. Based on the results, the highest stability was observed when the CO2 and N2 molecules approached the γ-graphyne sheet in a hollow space. Oxygenation of γ-graphyne led to increased CO2 adsorption capacity compared to pristine γ-graphyne. This can be attributed to the interaction between the Pπ electrons of the carbon in graphyne and carbonyl groups with the unbonded electron pair of the oxygen in CO2, leading to a more significant interaction of CO2 with the γ-graphyne surface. Furthermore, no significant N2 absorption was observed for oxygenated γ-graphyne.

Novel Zn(II) and Ni(II) complexes, [Zn(MeOPic)2(H2O)2] and [Ni(MeOPic)2(H2O)2] (MeOHPic = 4‐methoxypyridine‐2‐carboxylic acid [4meOHPic]), have been prepared and characterized by X‐ray diffraction (XRD), Fourier transform infrared (FTIR), and ultraviolet–visible (UV–Vis) techniques. Crystal structure analysis demonstrated that the 4meOHPic ligand is coordinated as a two‐dentate ligand through N and O atoms to central metal ions, and both of the complexes have distorted octahedral coordination geometry. The DFT‐B3LYP/6‐311++G(d,p)/LanL2DZ level was executed to perform DFT calculations for the Zn(II) complex with singlet spin state and the Ni(II) complex with triplet spin state. The UV–Vis electronic absorption spectra and natural bonding orbital (NBO) analyses also demonstrated that ligand–ligand and metal–ligand charge transfer interactions occur in Zn(II) and Ni(II) complexes. However, static and frequency‐dependent first‐order hyperpolarizability (β) parameters were found to be low because of the centrosymmetric crystal structures. As for the second‐order hyperpolarizabilities, the quadratic electro‐optical Kerr effect γ (−ω;ω,0,0) and electric field induced second harmonic generation γ (−2ω;ω,ω,0) parameters were calculated as 13.04 × 10−36 and 2258.9 × 10−36 esu for Ni(II) complex. Accordingly, it was demonstrated that Ni(II) complex is a potential candidate for third‐order nonlinear optical (NLO) materials. [ABSTRACT FROM AUTHOR]

In this work, intra- and intermolecular halogen and chalcogen bonds (HlgBs and ChBs, respectively) present in the solid state of nucleic acids (NAs) have been studied at the RI-MP2/def2-TZVP level of theory. To achieve this, a Protein Data Bank (PDB) survey was carried out, revealing a series of structures in which Br/I or S/Se/Te atoms belonging to nucleobases or pentose rings were involved in noncovalent interactions (NCIs) with electron-rich species. The energetics and directionality of these NCIs were rationalized through a computational study, which included the use of Molecular Electrostatic Potential (MEP) surfaces, the Quantum Theory of Atoms in Molecules (QTAIM), and Non Covalent Interaction plot (NCIplot) and Natural Bonding Orbital (NBO) techniques. [ABSTRACT FROM AUTHOR]

In this work, α-Ag2WO4 particles with different cross-sections were obtained using the co-precipitation method at different synthesis temperatures. The samples were characterized by X-ray diffraction (XRD), field-scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The antimicrobial activity was analyzed using the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) methods against the Escherichia coli and Salmonella spp. gram-negative bacteria. The antimicrobial tests against Escherichia coli and Salmonella spp. indicated that concentrations of 2.5–5 mg/mL and 5 mg/mL completely inhibit its growth, respectively. The antimicrobial activity was analyzed employing band-edge positions for ROS generations and the superficial distribution of Ag+ species that contribute to antimicrobial activity. Quantum-chemical calculations were used at the DFT level to investigate the surface-dependent reactivity of α-Ag2WO4, and we demonstrated how the antimicrobial properties could be tailored by the geometry and electronic structure of the exposed surfaces, providing guidelines for the morphology design. [ABSTRACT FROM AUTHOR]

So far, the development of new iodoargentate-based hybrids, especially those compounds with metal complex cations, and the understanding of their structure–activity relationships have been of vital importance but full of challenges. Herein, using the in-situ-generated metal complex cations as structural directing agents, three new iodoargentate-based hybrids, namely, [Co(phen)3]Ag2PbI6 (phen = 1,10-phenanthroline; 1), [Ni(5,5-dmpy)3]Ag7I9·CH3CN (5,5-dmpy = 5,5-dimethyl-2,2-bipyridine; 2) and [Co(5,5-dmpy)3]Ag5I8 (3), have been solvothermally prepared and then structurally characterized. Compound 1 represents one new heterometallic Ag–Pb–I compound characteristic of the chain-like [Ag2PbI6]n2n− anions. Compound 2 features the straight one-dimensional (1D) [Ag7I9]n2n− anionic moieties, while compound 3 contains infrequent two types of curved [Ag5I8]n3n− anions. Optical properties reveal that the title compounds exhibit interesting semiconductor behaviors with the band gaps of 1.59–2.78 eV, which endow them with good photoelectric switching performances under the alternate light irradiations. We also present their Hirshfeld surface analyses, and the theoretical studies (band structures, density of states (DOS) and partial density of states (PDOS)). [ABSTRACT FROM AUTHOR]