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Utilizing NMR (1H-NMR and 13C-NMR), FT-IR, UV-Visible, and quantum chemical approaches by using the DFT technique, experiments on 2-phenylthioanline were carried out. The B3LYP method and the 6-311++G(d,p) basis set were used to optimize the molecular structure and vibrational modes. The ideal binding parameters match up well with the experimental binding parameters. VEDA successfully finished the assignments concerning the distribution of potential energy. The GIAO method was used to calculate shifts in the 1H-NMR and 13C-NMR, and the outcomes were compared to experimental spectra. The TDDFT approach and the CPCM solvent model were used to examine electronic properties such as UV-Vis (in the gas phase, methanol, Acetone, and DCM), and the results were compared to experimental UV-Vis spectra. The HOMO/LUMO energy values provide sufficient proof of such. Molecular docking and dynamic simulations were carried out with a 2HI4 protein target and gave the best result among the three proteins. [ABSTRACT FROM AUTHOR]

Thermodynamic characteristics are calculated for new products of the transformation of N,N‑dimethylhydrazine, the values of which can be used to reliably identify these compounds and predict their periods of retention. For the first time, the ideal gas–rigid rotator–harmonic oscillator approximation is used to predict entropies in the gas phase, and the Feller–Peterson–Dixon approach is used to obtain reliable enthalpies of formation in the gas phase for the considered compounds. Retention of the considered isomeric triazole derivatives under conditions of reverse phase high-performance liquid chromatography correlates well with the obtained values of thermodynamic characteristics. [ABSTRACT FROM AUTHOR]

[Display omitted] K-doped Mn–Ce solid solution catalysts were synthesized using a combination of coprecipitation and hydrothermal methods, demonstrating excellent performance in benzene oxidation. The catalyst K 1 Ce 5 Mn 5 exhibited comparable activity to noble metal catalysts, achieving a 90 % benzene conversion at approximately 194 ℃. Durable tests under dry and moist conditions revealed that the catalyst could maintain its activity for 50 h at 218 ℃ and 236 ℃, respectively. Characterization results indicated that the catalyst's enhanced activity resulted from the weakened Mn–O bonding caused by the introduction of K+, facilitating the activation of oxygen and its involvement in the reaction. CeO x , the main crystalline phase of Mn–Ce solid solutions, provided abundant oxygen vacancies for capturing and activating oxygen molecules for the weakened Mn–O structures. This conclusion was further supported by partial density of state analysis from density functional theory computations, revealing that the introduction of K+ weakened the orbital hybridization of Mn3d and O2p. Finally, in situ diffuse reflectance infrared Fourier-transform spectroscopy (in situ DRIFTS) studies on Ce 5 Mn 5 and K 1 Ce 5 Mn 5 catalysts suggested that the introduction of K+ promoted the conversion of adsorbed benzene. Furthermore, intermediate products were transformed more rapidly for K 1 Ce 5 Mn 5 compared to Ce 5 Mn 5. [ABSTRACT FROM AUTHOR]

In the field of organic solar cells, organic semiconductors with Y6‐based chemical structure and their corresponding quinoxaline‐based assemblies are settled down as promising materials in the field of OSCs. However, the chemical structure of Y6 derivatives does not allow an expansion in the electron‐withdrawing central core, in contrast to their quinoxaline‐based analogues. For this reason, herein, two different quinoxaline‐based A–D–A′–D–A derivatives with 2D π‐extended cores endowed with electroactive rylenimide moieties, named as Y6‐1Napht and Y6‐1Pery, are designed and synthesized. These enlarged fused‐ring electron acceptors (FREAs) allow to study the influence of the length of the ryleneimide moiety on its structural, optical, electrochemical, and thermal properties as well as the tailoring of the frontier molecular orbitals. These results are also supported by quantum chemical calculations and photoluminescence measurements that provide additional information about their thermal stability and the microstructure of the films. Finally, as a proof of concept and to study the influence of these chemical modifications on the central core, solar cells based on these π‐conjugated nonfullerene acceptors are fabricated. [ABSTRACT FROM AUTHOR]

• Action of biophotons and lasers on living beings. • Explanation of the influences of biofield therapies on cells. • Biofield effects on intercellular calcium concentration. • Quantum calculations on calcium biofield therapy effects. • Mechanistic model of biofield action on cells. A revision of several experimental results on cells shows that electromagnetic radiation, either produced by biofield therapy (BFT) or laser, induced an increase in intracellular free calcium concentration. An explanation of this phenomenon is proposed. Quantum chemistry calculations were performed on Ca2+ with different degrees of hydration with the DFT/r2SCAN-3c method together with the implicit solvation model SMD. Ca2+ dehydration energy by quantum calculations, in an aqueous medium, coincides with the experimental results of the energy of the photon emitted in biofield therapies and lasers. This strongly suggests that the increased intracellular free calcium concentration is because of calcium ion dehydration upon the application of radiation. The Ca2+ dehydration increases the membrane potential due to an augment of the net charge on Ca2+ and it moves near the membrane by the attraction of its negative ions. The voltage-dependent channels are also activated by this membrane potential. The increased intracellular Ca2+ concentration occurs with biofield therapy (BFT) or laser. A novel explanation is given based on resonance-induced Ca2+ dehydration with applied radiation, supported by experimental data and theoretical calculations. [ABSTRACT FROM AUTHOR]

In the field of organic solar cells, organic semiconductors with Y6‐based chemical structure and their corresponding quinoxaline‐based assemblies are settled down as promising materials in the field of OSCs. However, the chemical structure of Y6 derivatives does not allow an expansion in the electron‐withdrawing central core, in contrast to their quinoxaline‐based analogues. For this reason, herein, two different quinoxaline‐based A–D–A′–D–A derivatives with 2D π‐extended cores endowed with electroactive rylenimide moieties, named as Y6‐1Napht and Y6‐1Pery, are designed and synthesized. These enlarged fused‐ring electron acceptors (FREAs) allow to study the influence of the length of the ryleneimide moiety on its structural, optical, electrochemical, and thermal properties as well as the tailoring of the frontier molecular orbitals. These results are also supported by quantum chemical calculations and photoluminescence measurements that provide additional information about their thermal stability and the microstructure of the films. Finally, as a proof of concept and to study the influence of these chemical modifications on the central core, solar cells based on these π‐conjugated nonfullerene acceptors are fabricated.

The work aims to determine the kinetic parameters of reactions for production of light olefins via catalytic cracking reactions of C4–C6 n-alkanes based on the energy characteristics of the transition state using quantum chemical calculations. Cracking reactions of C4–C6 n-alkanes proceed via protolytic mechanism on the Brønsted acid sites of zeolite-containing catalysts. For kinetic studies in this work, the thermochemical parameters of the intermediate stages, including hydrocarbon adsorption and transition state were determined, then the activation energies and rate constants were determined over the temperature range of catalytic cracking process from 773 to 903 K (500–630 °C).The results showed that DFT method in combination with B3LYP and ωB97X-D functionals, and 3–21 G basis demonstrated quite high accuracy in determining thermochemical parameters, including enthalpy, entropy and Gibbs free energy at both energetic levels of adsorption and transition state. Then, modeling continued by calculations of activation energies and rate constants of reactions. Obtained kinetic parameters made it possible to determine the reactivity of hydrocarbons with different chain length. It was obtained that the rate constants of butane cracking reactions with the formation of ethylene are 54–90 times higher than the formation of propylene. The rate constants of pentane cracking reactions with the formation of butylene are on average 5 times higher than the formation of propylene. The rate constants for hexane cracking reactions with the formation of butylene are 2.9–3.7 times higher compared to the formation of propylene.

Detecting a non-zero electric dipole moment in a particle would unambiguously signify physics beyond the Standard Model. A potential pathway towards this is the detection of a nuclear Schiff moment, the magnitude of which is enhanced by the presence of nuclear octupole deformation. However, due to the low production rate of isotopes featuring such 'pear-shaped' nuclei, capturing, detecting and manipulating them efficiently is a crucial prerequisite. Incorporating them into synthetic diamond optical crystals can produce defects with defined, molecule-like structures and isolated electronic states within the diamond band gap, increasing capture efficiency, enabling repeated probing of even a single atom and producing narrow optical linewidths. In this study, we used density functional theory to investigate the formation, structure and electronic properties of crystal defects in diamond containing 229Pa , a rare isotope that is predicted to have an exceptionally strong nuclear octupole deformation. In addition, we identified and studied stable lanthanide-containing defects with similar electronic structures as non-radioactive proxies to aid in experimental methods. Our findings hold promise for the existence of such defects and can contribute to the development of a quantum information processing-inspired toolbox of techniques for studying rare isotopes. This article is part of the Theo Murphy meeting issue 'Diamond for quantum applications'. [ABSTRACT FROM AUTHOR]

Mineral oil undergoes several chemical and physical changes with temperature change and time of storage. The lubricating additives are widely applied to the engine lubrication to suppress undesirable base oil properties like pour point depressants and viscosity index (VI) improvers. The current study aimed to prepare lube oil additives by preparing terpolymers as follows: reacting acrylic acid with various linear alcohols (decanol, dodecanol, and hexadecanol), several alkyl acrylates can be produced. Different imides were produced as a result of the reaction of maleic anhydride with different amines (aniline, triethylenetetramine, and tetraethylenepentamine). Fourier transforms infrared spectroscopy (FTIR) was utilized for investigating the structures of prepared compounds. Various terpolymers were synthesized during the polymerization reaction of different imides, different alkyl acrylates, and octene. The molecular weights of all polymers were detected through the use of gel permeation chromatography (GPC). Thermal gravimetric analysis (TGA) was used to determine the thermal stability of the prepared terpolymers, and the results demonstrated that the prepared terpolymers had high heat resistance. Above 300°C, the polymers deteriorated. Shear-thinning is observed in the rheological behavior, which approaches perfect Newtonian behavior at a high shear rate. The terpolymers created lowered the pour point of oil to -24 in the case of polymer C2 and viscosity index is increased to 140 in the case of polymer C3. Quantum calculations prove that compound C3 has more atom capacity to receive electrons compared to A3, which allows the formation of hydrogen bonds with other monomers making the resultant polymer bulkier and hence giving oil higher viscosity index. [ABSTRACT FROM AUTHOR]

The Cu-doped titanium oxide (Cu/TiO2) nanocomposite was systematically prepared using the innovatively feasible incipient wet impregnation method. Notably, the samples were derived from the raw materials through water dilution only. The successful formation of the host anatase TiO2 phase was confirmed by the characteristic peaks observed in the acquired X-ray powder diffraction (XRD) spectrum, which displayed intense peaks attributed to Cu2+ scattering sites, indicating the formation of crystallite Cu/TiO2 nanostructures. Dielectric measurements revealed that Cu/TiO2 possesses a higher dielectric permittivity compared to undoped TiO2. The conductivity for both structures exhibited a decreasing trend with increasing temperature. Interestingly, the measured optical properties indicated that Cu/TiO2 exhibited the minimum energy gap and maximum refractive index. This was further validated by qualitative time-dependent density functional calculation on a stable structural model, which was confirmed through semi-empirical molecular dynamic calculations. Thus, we have demonstrated the capability of our innovatively feasible synthesis method to produce the industrially important Cu-doped TiO2.

By the importance of developing detection materials and devices, the current work was done to provide molecular insights into the exploration of amphetamine (AMP) adsorbents/sensors through the density functional theory (DFT) assessments of carbon (g-C) and boron nitride (g-BN) graphdiyne nanosheets. Since AMP could be very harmful in an overdose level, then its careful detection is very important for employing the appropriate emergency cares and activities. The optimization calculations were performed to stabilize the structures of singular models and their corresponding AMP@g-C and AMP@g-BN complex, in which a higher strength was found for the formation AMP@g-C complex. Bothe complexes were stable enough to be recognized based on their formations and also by monitoring the variations of frontier molecular orbital features. The results indicated that the formation of AMP@g-BN complex could be used for an immediately detection whereas the formations of AMP@g-C complex could be used for a timely detection. Both complexes were found reusable based on the formation of non-covalent interactions between the substances, in which the stabilities and molecular orbitals features proposed both of g-C and g-BN nanosheets as suitable adsorbent/sensor materials of AMP substance for developing novel detection materials and devices.

The purpose of this article is to present insights on the mechanisms of formation of methanimine (CH2 = NH) a simplest five-atom molecule from the hydrogenation reaction of HCN in cold interstellar clouds. Using density functional theory (DFT) and the coupled cluster approach (CC), we investigated the two chemical pathways associated to methanimine production processes in detail. As the surface of interstellar grains presents very low temperatures, we were interested in the effect that low temperatures might have on the reaction enthalpy and activation barriers by lowering the temperature from 300 to 5 K. We have also studied the effect of bulk ice water on the enthalpy and the free enthalpy of the reaction. To model the effect of the bulk ice environment, two strategies were used: the implicit approach and the explicit approach. The implicit approach describes the bulky effects of ice water using the polarizable continuum model (PCM); the dielectric constant of ice is taken equal to 600. The second approach is to explicitly consider one to four water molecules surrounding the reactants and products of each reaction. Our results show that the formation of methanimine by the hydrogenation reaction of HCN is possible at very low temperatures both in the gas phase and in the ice-water environment. The reaction rate constants were calculated in the temperature range from 300 to 50 K using the transition state theory (TST). [ABSTRACT FROM AUTHOR]

Poly (4-vinyl pyridine) cross-linked by 2%DVB quartenized by I−, Br−, N3− and SCN−; named [P4-VP]MI, [P4-VP]BBr, [P4-VP]MN3, [P4-VP]MSCN are synthesized and their effect as a new eco-friendly polymeric inhibitor on the corrosion process of St-37 in 1 M H2SO4 at ambient temperature was investigated. Fourier-transform infrared spectroscopy (FT-IR), energy dispersive X-ray (EDX) and scanning electron microscope (SEM) techniques are used to confirm formation and the structure of the inhibitors. Then, their ability as corrosion inhibitors are examined by theoretical computation as well as the experimental tests involving potentiodynamic polarization (PDP), weight-loss measurements and electrochemical impedance spectroscopy (EIS). According to the obtained results, all inhibitors can effectively protect carbon steel from corrosion and the inhibition efficiency increases as the concentration of inhibitor and reaching 91.08% at 0.04 g L−1 [P4-VP]MI in 1 M H2SO4 and the corrosion current density reduces from 398.11 × 10−6 A·cm−2 in the blank condition to 35.48 × 10−6 A·cm−2. The geometrical and electronic properties of poly(4-vinylpyridine) cross-linked with 2% divinyl benzene and its derivatives as well as their corrosion inhibition process on Fe (1 1 0) surface are investigated using density-functional theory (DFT) and molecular dynamics (MD) simulation in water solution. The results of comparing the inhibitory efficiency of polymers show that the order of inhibition is as follows: [P4-VP]MI > [P4-VP]BBr > [P4-VP]MN3 > P4-VP > [P4-VP]MSCN. [ABSTRACT FROM AUTHOR]

This paper is devoted to the evaluation of the hardware resources of computer systems for solving a computationally expensive problem such as the calculation of the probability distributions of statistics by the second multiplicity method based on Δ -exact approximations of samples with a size of 320–1280 characters and an alphabet power of 128–256 characters. The accuracy is Δ = 10 − 5 and the total solution time should not exceed 30 days or 2.592 × 10 6 seconds for 24/7 computing. Owing to the use of the properties of the second multiplicity method, the computational complexity of the calculations can be brought within the range of 9.68 × 10 22 − 1.60 × 10 52 operations with the number of tested vectors at 6.50 × 10 23 − 1.39 × 10 50 . The solution of this problem for the specified parameters of samples during the given time requires hardware resources which cannot be provided by modern computer technology such as processors, graphics accelerators and programmable logic integrated circuits. Therefore, in this paper, we analyze the possibilities of promising quantum and photon technologies for solving the problem with the given parameters. The main advantage of quantum computer systems is the high speed of calculations for all possible parameter values. However, quantum acceleration will not be achieved to calculate the probability distributions of statistics due to the need to check all the obtained solutions. Here, the number of obtained solutions corresponds to the dimension of the problem. In addition, due to the current development level of quantum hardware components, it is impossible to create and use 120 qubit quantum computers for the solution of the considered problem. Photon computers can provide high computation speeds at low power consumptions and require the smallest number of nodes to solve the considered problem. However, unsolved problems with the physical implementation of efficient memory elements and the lack of available hardware components make the use of photon computer technologies impossible for calculating the probability distributions of statistics in the near future (5–7 years). Therefore, it is most reasonable to use hybrid computer systems containing nodes of different architectures. To solve the problem on various hardware platforms (general purpose processors, GPUs and FPGAs) and configurations of hybrid computer systems, we suggest to use the architecture-independent high-level programming language SET@L. The language combines the representation of calculations as sets and collections (based on the alternative set theory of P. Vopenka), the absolutely parallel form of the problem represented as an information graph and the paradigm of aspect-oriented programming. [ABSTRACT FROM AUTHOR]

In this work, two novel well‐defined Cu (I) complexes of a Schiff base ligand are described. For this purpose, N, N′‐bis (trans‐cinnamaldehyde) ethylenediimine [C20H20N2] (L) and Cu (I) complex of the type [CuC20H20N2)PPh3Cl] (C1) and [Cu(C20H20N2)PPh3Br] (C2) were synthesised. IR, NMR, XRD and TGA analyses were used to characterise these compounds and single‐crystal X‐ray crystallography confirmed the structure of the compounds. The catalytic activity of the synthesised complexes was studied in azide‐alkyne click reaction (AAC) and the best reaction condition was 15 mol% catalyst, 30 min and 45°C in water, which can be considered moderate catalytic activity for the complexes. Material Studio 2017 software was used to obtain the geometry, energy, HOMO and LUMO of all structures by the quantum calculations (module DMol3 and LDA/PWC). The computational results showed catalyst C2 has more reactivity than catalyst C1, and the C1‐catalysed products form faster than the C2‐catalysed products exceptions 4a and 4b. Product 4b (resulting catalyst C2) is formed faster than product (4a). [ABSTRACT FROM AUTHOR]

A highly efficient and versatile synthetic approach for the synthesis of 4-(pyren-1-ylmethyl)-1-(d-glycosyloxy) phthalazine nucleosides 11a,b, 13, β-S-nucleosides 16, 18, 20, and acyclo C-nucleosides 23a,b, 24, 25 and 27a–f was described and fully characterized. Furthermore, a series of desired new nucleoside analogues containing Se of 4-(pyren-1-ylmethyl) phthalazine-1(2H)-selenone 28–33 were synthesized. The structures of all reported compounds were confirmed by IR, 1H-NMR, 13C-NMR, MS and elemental analysis. All compounds have been screened for their antibacterial and antifungal activities. Maximum activity was shown by 20 and 33a comparable to the standard drugs with lower toxicity. The cytotoxicity of the selected compound was measured and evaluated. The energy gap between the highest occupied molecular orbital and lowest unoccupied molecular orbital was calculated using theoretical computations to reflect the chemical reactivity and kinetic stability of the synthesized compounds. Using density functional theory (DFT), electronic parameters such as the highest occupied and lowest unoccupied molecular orbitals (HOMO and LUMO) and the molecular electrostatic potential (MEPS) were calculated. On the basis of different studied structures, these properties were computed in order to elucidate the chemical reactivity and the kinetic stability. Obviously, the band gap energy (Eg) of structures studied reveals that the lowest band gap obtained for the structure 16-a indicates that it has the highest chemical reactivity and lowest kinetic stability. [ABSTRACT FROM AUTHOR]

[Display omitted] • The contributions of HO•, Cl• and ClO• species for CBZ degradation were quantified. • HO• attack CBZ by hydrogen atom transfer and radical adduct formation mechanisms. • Cl• attack CBZ mainly by hydrogen atom transfer mechanism. • ClO• attack CBZ mainly by radical adduct formation mechanism. • DFT calculations confirmed the main products formation pathways of CBZ degradation. Carbamazepine (CBZ) is a ubiquitous persistent micropollutant in water. This study evaluated the degradation of CBZ by UV/Chlorine process. The influencing factors, such as chlorine dosage, solution pH, and water matrix constituents (Cl−, HCO 3 – and NOM) on CBZ removal were systematically investigated. The reactive HO•, Cl• and ClO• species were mainly responsible for the degradation of CBZ, and their contributions determined by probes (Benzoic acid, Nitrobenzene and 1,4-Dimethoxybenzene) varied with pH. Theoretical quantum calculations involving a total of 79 transition states suggested that HO• attack CBZ by hydrogen atom transfer (HAT) and radical adduct formation (RAF) mechanisms, while Cl• and ClO• proceed mainly through HAT and RAF mechanism, respectively. The reaction rates between CBZ and free radicals were calculated by evaluating the energy barriers and transition states. Furthermore, the proposed formation pathways and reaction mechanisms of main hydroxylated products and chlorine substituted products were unequivocally authenticated by transition states calculations. Overall, this study combined experimental and computational approaches to provide an in-depth degradation mechanism of CBZ in UV/Chlorine process. [ABSTRACT FROM AUTHOR]

• The effect of [H+] on the aqueous oxidation of pyrite was investigated. • The reaction order with respect to [H+] is 0.05 ± 0.10. • The H+ is not involved in the rate determining step of FeS 2 oxidation. The reaction of pyrite (FeS 2) with dissolved oxygen (DO) in acidic media (pH 2.5, 3.0 and 4.0) was studied at 25 °C. In this regard, a series of experimental (potentiodynamic polarization, Electrochemical Impedance Spectroscopy (EIS) or cyclic voltammetry) and theoretical (quantum calculations) approaches were used. It was found that the proton concentration ([H+]) has not a significant influence on the oxidative dissolution of FeS 2. The oxidation current density (j ox) varies little when the pH increases from 2.5 (j ox = 1.02 μA cm−2) to 4.0 (j ox = 0.80 μA cm−2), the order of reaction with respect to [H+] being 0.05 ± 0.10. EIS spectra indicate that the pyrite oxidation with dissolved oxygen is controlled by a surface electron transfer reaction. The results of quantum calculations show that protons spontaneously adsorb to the pyrite surface. The density of states of adsorbed protons is located far from Fermi level (between −0.3 and −0.2 Hartree) indicating that they are not available for subsequent reactions. The results of quantum analysis outline the main reasons why protons do not play a discernible role in the oxidation of pyrite with DO and the formation of acid mine drainage. [ABSTRACT FROM AUTHOR]

[Display omitted] • A dose of 7.5 × 10−4 M demonstrated a high effectiveness level, surpassing 97 %. • Adsorption studies indicated that PAEOD chemically adheres according to the Langmuir isotherm. • SEM analysis confirmed the formation of a protective PAEOD layer on the steel. • DFT and MC/MD studies revealed that the PAEOD compound binds to the steel substrate. • Anti-SRB and docking simulations showed that PAEOD impacts the growth of SRB. This paper examines the innovative application of PAEOD as a corrosion suppressant for steel in an acidic environment with a concentration of 1.0 M HCl. The inhibitory potential of PAEOD has been comprehensively evaluated through the utilization of diverse analytical approaches, including electrochemical tests, gravimetric analysis, and scanning electron microscopy (SEM) assessments. The results suggest that there is a correlation between concentration and the enhancement of corrosion resistance, hence categorizing PAEOD as a mixed-type inhibitor. The maximum inhibitory efficiency was observed at a concentration of 7.50 × 10-4 M, resulting in a remarkable efficiency of 98.84 % at a temperature of 298 K. The electrochemical investigation demonstrated a significant rise in the values of charge transfer resistance (R ct) and polarization resistance (R p), accompanied by a reduction in the Constant Phase Element (CPE. Yo) value to 74.01 μF. These findings suggest an improved capacity for inhibiting corrosion. Theoretical studies have revealed a significant interaction between PAEOD and the steel surface, as evidenced by the utilization of density functional theory (DFT) and Monte Carlo/ Molecular dynamic (MC/MD) techniques. This interaction indicates the presence of exceptional anti-corrosion properties at the micro-level. The impact of PAEOD on the growth of sulphate reducing bacteria (SRB) was found to be substantial, as indicated by the findings derived from BART™ Vials. In summary, this work establishes PAEOD as a potentially effective corrosion inhibitor, offering significant contributions to the field of corrosion prevention strategies through its important insights. [ABSTRACT FROM AUTHOR]

Metal corrosion is a destructive process for many industrial operations, including oil well acidizing and acid pickling. Therefore, numerous efforts made by many researchers to control the steel corrosion. In the present work, A (E)-4-(((4-(5-mercapto-1,3,4-oxadiazol-2-yl) phenyl) amino) methyl)-2-methoxyphenol (MOPM) has been synthesized and characterized as a new corrosion inhibitor for mild steel in 0.1 M hydrochloric acid. FTIR and 1HNMR were used in the diagnosis of MOPM, while electrochemical polarization technique was employed to test the performance of inhibitor at various temperatures and inhibitor concentrations. Electrochemical studies showed that MOPM acts as a mixed-type inhibitor with a maximum inhibition efficiency of 93.2% at 30 °C and 0.5 M MOPM. Furthermore, the presence of MOPM increased the polarization resistance and depressed the corrosive action. The inhibitory action of MOPM over mild-steel surface was according to Langmuir adsorption isotherm. The calculated free energy of adsorption was −20.663 kJ.mol−1 that suggested the spontaneous physical adsorption mode. Value of activation energy was higher in the presence of MOPM, which indicated the formation of protective layer on the metal surface. Quantum chemical calculations that carried out to the chemical structure of MOPM provides a reasonable support to the experimental results.

The corrosion of industrial material is a costly problem associated with global economic losses reaching trillions of US dollars in the repair of failures. Injecting corrosion inhibitors is the most practically promising method for decelerating corrosion reactions and protecting surfaces. Recent investigations have focused on surfactants as corrosion inhibitors due to their amphiphilic nature, low cost, and simple chemical preparation procedures. This study aims to investigate the performance of an environment-friendly Quaternium-22 (Q-22) surfactant which is widely used in cosmetics for C-steel corrosion inhibition in a 5 M HCl medium. Weight loss experiments were performed at different concentrations and immersion times, presenting a maximum efficiency at 2.22 mmol·L−1. The influence of Q-22 on the corrosion behavior of C-steel was elucidated using non-destructive electrochemical measurements. The overall results revealed that adding varied concentrations of Q-22 significantly decreases the corrosion rate of C-steel. The results revealed the physisorption nature of Q-22 onto the C-steel surface, with adsorption following the Freundlich isotherm (∆ H ads = −16.40 kJ·mol−1). The relative inhibition performance of Q-22 was also evaluated by SEM and AFM analyses. Lastly, quantum chemical calculations based on density functional theory (DFT) demonstrated that Q-22 has promising molecular features concerning the anticorrosive mechanism. [ABSTRACT FROM AUTHOR]

Due to numerous pharmaceutical and biological activities hydrazone (TC) based materials, it was important to investigate quantum chemical studies such as Density functional theory (DFT) calculations, natural bond orbital (NBO) analysis, molecular electrostatic potential (MESP), and local reactivity usage Fukui function for six TC derivatives compounds. DFT, NBO, MESP, and local reactivity calculations were obtained via utilizing CAM-Becke's three-parameter functional and Leee Yange Parr (CAM-B3LYP) functional and 6-311G + + (2d, 2p) basis set. Optimized molecular structures for all studied compounds were obtained usage the DFT/CAM-B3LYP/6-311G + + (2d, 2p) method. In addition, the highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO), energy gap (Eg), light harvest efficiency (LHE), and open-circuit voltage (Voc) of all studied MSs are calculated and illustrated. These properties indicate that these molecular modeling structures as good candidates for utilization in organic DSSCs. The calculated spectroscopic investigations of hydrazine derivatives have been obtained by applying the TD/CAM-B3LYP/6-311G + + (2d, 2p) method. the calculated UV–Vis absorption spectra for molecular structures under study show nice correlations with experimental spectra. [ABSTRACT FROM AUTHOR]

This paper is devoted to the evaluation of the hardware resources of computer systems for solving a computationally expensive problem such as the calculation of the probability distributions of statistics by the second multiplicity method based on Δ-exact approximations of samples with a size of 320–1280 characters and an alphabet power of 128–256 characters. The accuracy is Δ=10−5 and the total solution time should not exceed 30 days or 2.592×106 seconds for 24/7 computing. Owing to the use of the properties of the second multiplicity method, the computational complexity of the calculations can be brought within the range of 9.68×1022−1.60×1052 operations with the number of tested vectors at 6.50×1023−1.39×1050. The solution of this problem for the specified parameters of samples during the given time requires hardware resources which cannot be provided by modern computer technology such as processors, graphics accelerators and programmable logic integrated circuits. Therefore, in this paper, we analyze the possibilities of promising quantum and photon technologies for solving the problem with the given parameters. The main advantage of quantum computer systems is the high speed of calculations for all possible parameter values. However, quantum acceleration will not be achieved to calculate the probability distributions of statistics due to the need to check all the obtained solutions. Here, the number of obtained solutions corresponds to the dimension of the problem. In addition, due to the current development level of quantum hardware components, it is impossible to create and use 120 qubit quantum computers for the solution of the considered problem. Photon computers can provide high computation speeds at low power consumptions and require the smallest number of nodes to solve the considered problem. However, unsolved problems with the physical implementation of efficient memory elements and the lack of available hardware components make the use of photon computer technologies impossible for calculating the probability distributions of statistics in the near future (5–7 years). Therefore, it is most reasonable to use hybrid computer systems containing nodes of different architectures. To solve the problem on various hardware platforms (general purpose processors, GPUs and FPGAs) and configurations of hybrid computer systems, we suggest to use the architecture-independent high-level programming language SET@L. The language combines the representation of calculations as sets and collections (based on the alternative set theory of P. Vopenka), the absolutely parallel form of the problem represented as an information graph and the paradigm of aspect-oriented programming.

Herein, a simple approach was formed based on synthesizing different morphologies of ZnO and Au-ZnO as photocatalyst. In this study, ZnO and Au-ZnO were synthesized via a co-precipitation method and fully characterized via scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy-dispersive X-ray spectroscopy (EDX). Three different ratios of Zn2+:OH− (1:2, 1:3, and 1:5) controlled the morphology of samples, which were made into spindle, star, and flower structures, respectively. Then, the photocatalytic activity was studied and compared. Their comparison showed that the flower morphology for ZnO and Au-ZnO was more effective in photocatalytic degradation and decolorization of methyl orange dye. Also, quantum and Monte Carlo (MC) calculations were carried out to investigate the adsorption of methyl orange (MO) molecules on ZnO(111) surface in the presence of Au or without Au in aqueous conditions by Monte Carlo adsorption locator simulations in the Materials Studio 2017 software. Au created a tendency to form a relatively strong interaction of MO with the ZnO(111) surface. The adsorption of MO on Au-ZnO(111) in the presence of Au was more significant than that of MO on ZnO(111), suggesting Au could significantly improve the reactivity of the methyl orange toward the ZnO(111). [ABSTRACT FROM AUTHOR]

Acidic reactions of uranyl cations in solution? [Display omitted] • "Multiple Minima Hypersurface (MMH)" approach results as a reliable theory to model structures and energetics of uranyl cations in water. • MMH approach can predict equilibria, hydrolysis and the populations of different uranyl-water species on the energy hypersurface. • Criteria for predicting the behavior of uranyl compounds in uranium mining waste interacting with soil/sediments can be established. • Results harness further develop the MMH methodology for studying actinide compounds by using reliable quantum tools. The multiple minima hypersurface (MMH) approach is a reliable theoretical model for characterizing uranyl-water complexes in aqueous media. It provides insights into probable conformations, solubility, and reactivity through accurate exploration of the local energy landscape via quantum calculations. The approach predicts equilibria and populations of local minima, identifying pre-reactive sites and hydrolyzed ligands. By applying MMH to a wider range of molecular species, a robust theoretical framework is established for understanding the complex chemistry of environmental and nuclear materials. The approach here aims to predict the behavior of weathered uranium mining waste and enhance the study of actinide compounds. [ABSTRACT FROM AUTHOR]

[Display omitted] • An extensive review of computational catalysis and machine learning approaches. • Key principles of machine learning potential construction are explained. • Dataset construction, representation, model architecture & evaluation are covered. • Recent advancements in catalyst research through MLP-based multiscale simulations. • Also, major hurdles are tackled in the area. The urgency of tackling climate change is driving a global shift towards renewable sources of energy, with a growing contribution from alternative energy sources such as solar, wind and hydroelectric power. With the global push for the sustainable energy, the demand for effective catalysts for sustainable chemical production and energy storage has been rapidly increasing. Computational simulations have contributed to the rational design of catalysts by allowing profound analysis of catalyst properties. Machine learning potential (MLP) has emerged as a potential tool to bridge the gap between quantum mechanical accuracy and computational efficiency, overcoming the computational cost limitations of quantum chemistry-based simulations. This review discusses the development and application of MLP in multiscale simulations of heterogeneous catalysis. It covers the basic concepts of computational catalysis, the construction of MLP focusing on efficient datasets, atomic structure representations, and the process of training and evaluating of ML models. Furthermore, the potential applications of MLP are discussed in addressing computational challenges within the field, as MLP has potential to overcome limitations in simulation time and length scale. Lastly, the prospects for MLP are presented, taking advantage of the rapid advancements in artificial intelligence architectures. It is expected that the integration of MLP will accelerate progress within the catalyst research community and will bridge the gap between theoretical and experimental approaches in catalytic research. [ABSTRACT FROM AUTHOR]

The article defines the criteria for choosing a cloud-based platform for mastering the basics of quantum informatics by students of a specialized (high) schools: cross-browser; intuitive interface; the possibility of free access; access without registration and simplified registration; the presence of a systematized reference system with examples; support for the development of the environment by the developer; support for working in a personal educational environment; support for working with quantum algorithms in graphical mode; automatic conversion of quantum algorithms from graphic format to program code text; support for the Ukrainian-language localization; availability of a mobile application; responsive design. The possibilities of platforms for implementing quantum algorithms from the following companies are analyzed: Microsoft, QuTech, Amazon Braket, IBM. The choice of the IBM Quantum cloud-based platform is justified. Work at IBM Quantum Composer and IBM Quantum Lab is described. Information about quantum operations and gates is presented: their designation in IBM Quantum Composer and IBM Quantum Lab, the gate matrix, and the purpose of the gate. An example of implementing quantum teleportation in the form of a circuit and program is given.

We report full-dimensional and fully coupled quantum bound-state calculations of the J=1 intra- and intermolecular rovibrational states of two isotopologues of the hydrogen chloride-water dimer, HCl-H2O (HH) and DCl-H2O (DH). The present study complements our recent theoretical investigations of the J=0 nine-dimensional (9D) vibrational level structure of these and two other H/D isotopologues of this noncovalently bound molecular complex, and employs the same accurate 9D permutation invariant polynomial-neural network potential energy surface. The calculations yield all intramolecular vibrational fundamentals of the HH and DH dimers and the low-energy intermolecular rovibrational states in these intramolecular vibrational manifolds. The results are compared with those of the 9D J=0 calculations of the same dimers. The energy differences between the K=1 and K=0 eigenstates exhibit pronounced variations with the intermolecular rovibrational states, for which a qualitative explanation is provided. [ABSTRACT FROM AUTHOR]

A highly efficient and versatile synthetic approach for the synthesis of 4-(pyren-1-ylmethyl)-1-(d-glycosyloxy) phthalazine nucleosides 11a,b, 13, β-S-nucleosides 16, 18, 20, and acyclo C-nucleosides 23a,b, 24, 25 and 27a–f was described and fully characterized. Furthermore, a series of desired new nucleoside analogues containing Se of 4-(pyren-1-ylmethyl) phthalazine-1(2H)-selenone 28–33 were synthesized. The structures of all reported compounds were confirmed by IR, 1H-NMR, 13C-NMR, MS and elemental analysis. All compounds have been screened for their antibacterial and antifungal activities. Maximum activity was shown by 20 and 33a comparable to the standard drugs with lower toxicity. The cytotoxicity of the selected compound was measured and evaluated. The energy gap between the highest occupied molecular orbital and lowest unoccupied molecular orbital was calculated using theoretical computations to reflect the chemical reactivity and kinetic stability of the synthesized compounds. Using density functional theory (DFT), electronic parameters such as the highest occupied and lowest unoccupied molecular orbitals (HOMO and LUMO) and the molecular electrostatic potential (MEPS) were calculated. On the basis of different studied structures, these properties were computed in order to elucidate the chemical reactivity and the kinetic stability. Obviously, the band gap energy (Eg) of structures studied reveals that the lowest band gap obtained for the structure 16-a indicates that it has the highest chemical reactivity and lowest kinetic stability.

Collisional cross-sections of inelastic rotational excitations of CN in its ground electronic state (X2Σ+) by H+ scattering are studied by the exact quantum mechanical close-coupling (CC) method at very low collision energies (0–600 cm−1) relevant to interstellar atmospheres. Ab initio rigid rotor potential energy surface computed at MRCI/cc-pVTZ level of accuracy has been employed. Rate coefficients for the rotational excitations have also been calculated. The obtained results are compared with previous theoretical calculations and analyzed whether proton collisions could be significant sources for rotationally excited CN as a possible source for cosmic microwave background of about 3 K from the interstellar media.

The corrosion of industrial material is a costly problem associated with global economic losses reaching trillions of US dollars in the repair of failures. Injecting corrosion inhibitors is the most practically promising method for decelerating corrosion reactions and protecting surfaces. Recent investigations have focused on surfactants as corrosion inhibitors due to their amphiphilic nature, low cost, and simple chemical preparation procedures. This study aims to investigate the performance of an environment-friendly Quaternium-22 (Q-22) surfactant which is widely used in cosmetics for C-steel corrosion inhibition in a 5 M HCl medium. Weight loss experiments were performed at different concentrations and immersion times, presenting a maximum efficiency at 2.22 mmol·L−1. The influence of Q-22 on the corrosion behavior of C-steel was elucidated using non-destructive electrochemical measurements. The overall results revealed that adding varied concentrations of Q-22 significantly decreases the corrosion rate of C-steel. The results revealed the physisorption nature of Q-22 onto the C-steel surface, with adsorption following the Freundlich isotherm (∆Hads= −16.40 kJ·mol−1). The relative inhibition performance of Q-22 was also evaluated by SEM and AFM analyses. Lastly, quantum chemical calculations based on density functional theory (DFT) demonstrated that Q-22 has promising molecular features concerning the anticorrosive mechanism.

The article defines the criteria for choosing a cloud-oriented platform for mastering the basics of quantum informatics by students of a specialized (high) school: cross-browser; intuitive interface; the possibility of free (free) access; access without registration and simplified registration; the presence of a systematized reference system with examples; support for the development of the environment by the developer; support for working in a personal educational environment; support for working with quantum algorithms in graphical mode; automatic conversion of quantum algorithms from graphic format to program code text; support for the Ukrainian-language locale; availability of a mobile application; responsive design. The possibilities of platforms for implementing quantum algorithms from the following companies are analyzed: Microsoft, QuTech, Amazon Braket, IBM. The choice of the IBM Quantum Cloud-based platform is justified. Work at IBM Quantum Composer and IBM Quantum Lab is described. Information about quantum operations and Gates is presented: their designation in IBM Quantum Composer and IBM Quantum Lab; the gate Matrix; and the purpose of the gate. An example of implementing quantum teleportation in the form of a scheme and program is given.

The process of quantum tomography of polarization-entangled photon pairs was simulated on quantum computers of different generations of the IBM Q Experience platform. The simulation was carried out for all four two-qubit Bell states. It turned out that the contribution of basis states that are absent in Bell states does not exceed 10 even on quantum computers of the first generations, and is reduced to several percent on quantum computers of the latest generation. The simulation quality was evaluated using Fidelity. The Fidelity values were in a range of 68.6–94.9 , depending on the generation of computers. It was shown that for Bell states Fidelity can be calculated using three tomographic measurements instead of the nine required for determination of the density matrix using quantum state tomography. [ABSTRACT FROM AUTHOR]

Introduction: A revision of several experimental results on cells shows that electromagnetic radiation, either produced by biofield therapy (BFT) or laser, induced an increase in intracellular free calcium concentration. An explanation of this phenomenon is proposed., Methods: Quantum chemistry calculations were performed on Ca 2+ with different degrees of hydration with the DFT/r 2 SCAN-3c method together with the implicit solvation model SMD., Results: Ca 2+ dehydration energy by quantum calculations, in an aqueous medium, coincides with the experimental results of the energy of the photon emitted in biofield therapies and lasers. This strongly suggests that the increased intracellular free calcium concentration is because of calcium ion dehydration upon the application of radiation. The Ca 2+ dehydration increases the membrane potential due to an augment of the net charge on Ca 2+ and it moves near the membrane by the attraction of its negative ions. The voltage-dependent channels are also activated by this membrane potential., Conclusion: The increased intracellular Ca 2+ concentration occurs with biofield therapy (BFT) or laser. A novel explanation is given based on resonance-induced Ca 2+ dehydration with applied radiation, supported by experimental data and theoretical calculations., (Copyright © 2023. Published by Elsevier Inc.)

Herein, it is demonstrated that a small amount (0.05% in weight ratio) of polyethyleneimine (PEI) can effectively suppress the "burn‐in" degradation of both PTB7‐Th:PC61BM and P3HT:PC61BM cells, similar to the piperazine derivatives, suggesting that organic amines can serve as universal stabilizer in polymer:PC61BM solar cells. Light‐induced electron spin resonance (LESR) spectroscopy measurement shows a higher ESR signal intensity of PC61BM anions in 0.2% PEI‐doped film than in 1% piperazine‐doped film. Moreover, no piperazine is detected in a 10% (w/w) piperazine‐doped film by gas chromatography–mass spectrometry (GSMS). These results suggest that the residual piperazine in the blend film is very low, which can be understood by the high volatility of piperazine. Quantum calculations are performed on the intermolecular binding energy (EB) between polymer (using model repeating units), PC61BM, and piperazine molecules. Results reveal that piperazine prefers to localize at the polymer:fullerene interface by complexing with PC61BM (in P3HT:PC61BM) or PTB7‐Th (in PTB7‐Th:PC61BM system), which indicates that the photo dimerization of PC61BM which causes the "burn‐in" degradation of polymer:fullerene solar cells mainly happens at the donor/acceptor interface, and the organic amine serves as the targeting stabilizer at the interface. [ABSTRACT FROM AUTHOR]

The integration of instruction and research represents one of the fundamental goals of contemporary educational system. Elaborating effective mechanisms for applying research methods able to make science more attractive could solve the problem of motivating young people to study in this difficult but necessary field for society development. The study proposes a model of using chemical synthesis, studying molecular structure and composition of coordination compounds, applying quantum-chemical calculations and testing biological properties. The set of applied methods allows for a detailed analysis of certain features related to the structure and properties of new chemical compounds and is recommended for application within university courses and at pre-university level- for interested students.

Twenty-one pentafluorphenylhydrazones have been analyzed by means of tandem mass spectrometry (ESI MS/MS) conditions to compare their fragmentations with those ones obtained from quantum-chemical calculations of the hydrazone moiety depending on the substitution from the aldehyde site. The hydrazone N--N bond is disrupted under such conditions, and these results are in accordance with the facts that an electron-rich particle, such as an anion and or radical in a solution, can cause this disruption and simultaneous defluorination in para-position of the hydrazone part of the molecule. [ABSTRACT FROM AUTHOR]

Chemical reaction networks are essential for the complete elucidation of chemical reaction mechanisms. Graph‐theoretic methods combined with quantum calculations are known to be an efficient approach with broad applicability for constructing reaction networks. However, this method entails high computational cost due to quantum calculations on chemically irrelevant intermediates coming from the exploration of a large scale chemical space. To remedy this problem, we propose to apply the Monte Carlo tree search algorithm to those graph‐theoretic methods. We have combined it with ACE‐Reaction, our in‐house graph‐theoretic method, and demonstrated its performance on five organic reactions. The result shows that the computational cost for quantum calculations has been reduced by up to 75 % from that of the original ACE‐Reaction. Furthermore, cost reduction became more efficient for more complex reactions. [ABSTRACT FROM AUTHOR]

Paramagnetic ions having two electrons and spin S = 1 in zero magnetic field are proposed for new physical performance of elementary quantum computing operations by pulsed manipulations with electron spins. For this purpose, a new type of microwave pulses with variable phases and different polarizations are shown can be used. Such pulses are able to induce different transitions between ion spin states. Some of those transitions are described by operators similar to quantum computing operators. To describe the effects of such pulses on hig-spin ions, a new way to represent exponential operators as polynomials of the Pauli matrices is proposed. [ABSTRACT FROM AUTHOR]

• Adsorption mode of Sildenafil at 6063 Aluminum Alloy is investigated. • Sildenafil is an eco-friendly inhibitor for 6063 Aluminum Alloy. • The adsorbability of is dependent on the medium. • Quantum calculations correlates well with the experimental results. The corrosion inhibition of aluminum alloy surface (6063AA) by Sildenafil (SIL) in 1 M for both HCl and NaOH solutions was investigated using weight loss, electrochemical techniques and quantum calculations. The inhibitory effect of SIL was explained by the formation of the complex adsorbed on the 6063AA surface. The adsorption obeyed Langmuir isotherm. The adsorption of the SIL is a mix of physical and chemical adsorption, where the free energy of adsorption was found to equal −39.12 and −34.6 KJ/mol, in HCl and NaOH, respectively. Experimental outcomes showed that SIL significantly inhibits the dissolution of 6063Al in both acidic and alkaline media. SIL drug acts as a mixed inhibitor in both two aggressive solutions. The correlation of the inhibition performance of SIL on 6063Al with the molecular structure was adopted using Dmol3 (Materials Studio v7. 0) based on some descriptors as E HOMO and E LUMO. Fukui indices were computed to determine the active sites of the inhibitor molecules. The equilibrium adsorption behavior of SIL on Al (1 1 1) surface was examined using molecular dynamics simulation. The quantum chemical descriptors were found suitable in explaining the inhibitive action of SIL. [ABSTRACT FROM AUTHOR]

Long emission wavelengths, high fluorescence quantum yields (FQYs), and large Stokes shifts are highly desirable features for fluorescent probes in biological imaging. However, the current development of many fluorescent probes remains largely trial‐and‐error and lacks efficiency. Moreover, to achieve far‐red/near‐infrared emission, a significant extension in the π ‐conjugation is usually adopted but accompanied by other drawbacks such as fluorescence loss. In this review, we discuss an effective red‐shifting strategy built upon the green fluorescent protein chromophore, which enables a synergistic tuning of both the electronic ground and excited states. This approach could shorten the path toward redder emission in comparison to the conventional intramolecular charge transfer (ICT) strategy. We envision that this spectroscopy and computation‐aided strategy may advance the noncanonical fluorescent protein design and be generalized to various fluorophore scaffolds for redder emission while preserving other superior properties such as high FQYs. [ABSTRACT FROM AUTHOR]

Chiral separation is an important issue for the pharmaceutical industry. Over the years, several separation methods have been developed, mainly based on chromatography. Their working principle is based on the formation of transient diastereoisomers, but the very subtle nanoscale interactions responsible for separation are not always understood. Recently, Raman and surface-enhanced Raman (SERS) spectroscopy have provided promising results in this field. Here we present Raman/SERS experimental data that provide useful information concerning the nanoscale interactions between propranolol enantiomers and α, β, and γ cyclodextrins. Raman spectroscopy was used to prove the formation of host–guest intermolecular complexes having different geometries of interaction. The occurrence of new vibrational bands and a change in the intensities of others are direct proofs of complexes’ formation. These observations were confirmed by DFT calculations. By performing SERS measurements on a new type of plasmonic substrate, we were able to prove the intermolecular interactions responsible for PRNL discrimination. It turned out that the interaction strength between the substrate and the intermolecular complexes is of paramount importance for SERS-based chiral discrimination. This approach could represent a very good starting point for the evaluation of molecular interactions manifesting between other pharmaceutical compounds and different classes of chiral selectors.

The study of the dynamics of atom–diatom reactions involving two rare gas (Rg) atoms and protons is of crucial importance given the astrophysical relevance of these processes. In a series of previous studies, we have been investigating a number of such Rg(1)+ Rg(2)H+→ Rg(2)+ Rg(1)H+ reactions by means of different numerical approaches. These investigations comprised the construction of accurate potential energy surfaces by means of ab initio calculations. In this work, we review the state-of-art of the study of these protonated Rg systems making special emphasis on the most relevant features regarding the dynamical mechanisms which govern these reactive collisions. The aim of this work therefore is to provide an as complete as possible description of the existing information regarding these processes.