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Four acridinium/acridine derivatives have been prepared by mechanochemical synthesis and their crystal structure, supramolecular framework, interaction energy calculation, thermal analysis, and photophysical properties are studied and presented in this manuscript. In the crystal structure, the one- and two-dimensional supramolecular framework is constructed via various strong and weak intermolecular interactions such as N‒H...Cl, O‒H...N, O‒H...Cl, C‒H...Cl, C‒H...O, C‒H...π, and π...π, respectively. The contribution of intermolecular interaction in the three-dimensional molecular packing is studied by the Hirshfeld surface analysis. The calculated total energy value of intermolecular interaction/contacts observed between the molecular pairs in the acridine compound is stronger than the energy value of intermolecular interaction/contacts of acridinium derivatives. The energy value of π...π contacts exhibited between the molecular pairs is significantly stronger than other weak interactions. The thermogravimetric analysis reveals that the acridinium derivatives degrade in three steps whereas the acridine compound undergoes a single-step degradation. Studies show that the acridinium derivatives exhibit a better photoluminescence quantum yield when compared to the acridine compound, and the acridine compound experiences a photoluminescence quenching due to charge transfer interactions. [ABSTRACT FROM AUTHOR]

To investigate the mechanism underlying the effect of mixed collector (MC) composed of diesel and span-80 on LRC flotation, a combination of experimental and molecular simulation approaches was employed. The flotation results demonstrated that the use of MC yielded superior flotation performance compared to diesel alone. The ratio of diesel to span-80 emerged as a key factor influencing the performance of MC collection. Furthermore, molecular dynamics (MD) simulations were employed to investigate the adsorption processes of dodecane and MC molecules on the LRC surface in the LRC/dodecane/water and LRC/MC/water systems, respectively. The analysis encompassed microstructure, dynamic properties, interaction energy, and hydrogen bonding. The findings indicated that the presence of span-80 molecules facilitated the direct entry of dodecane molecules in MC into "microscopic cavities," thereby enhancing the adsorption of MC on the LRC surface. The analysis of interaction energy revealed a stronger interaction between MC molecules and the coal surface, with van der Waals energy playing a major role in the adsorption process. Additionally, span-80 molecules induced hydrogen bonding adsorption on the LRC surface. [ABSTRACT FROM AUTHOR]

We introduce the fragment‐pairwise Local Energy Decomposition (fp‐LED) scheme for precise quantification of individual interactions contributing to the binding energy of arbitrary chemical entities, such as protein‐ligand binding energies, lattice energies of molecular crystals, or association energies of large biomolecular assemblies. Using fp‐LED, we can assess whether the contribution to the binding energy arising from noncovalent interactions between pairs of molecular fragments in any chemical system is attractive or repulsive, and accurately quantify its magnitude at the coupled cluster level ‐ commonly considered as the “gold standard” of computational chemistry. Such insights are crucial for advancing molecular and material design strategies in fields like catalysis and therapeutic development. Illustrative applications across diverse fields demonstrate the versatility and accuracy of this theoretical framework, promising profound implications for fundamental understanding and practical applications. [ABSTRACT FROM AUTHOR]

We have investigated the basic mechanism of carbon nanotube (CNT) interactions with various room-temperature ionic liquids (RTILs) using molecular dynamics (MD) simulations. To understand the effects of the cation molecular geometry on the properties of the interface structure in the RTIL systems, we have studied a set of three RTILs with the same [BF4]- (tetrafluoroborate) anion but with different cations, namely, [EMIM]+ (1-ethyl-3-methylimidazolium), [BMIM]+ (1-butyl-3-methylimidazolium), [HMIM]+ (1-hexyl-3-methylimidazolium), and [OMIM]+ (1-octyl-3-methylimidazolium) ions. The simulation results showed that the imidazolium cations exhibit two distinct orientations (perpendicular and parallel to the CNTs surface) at the interface irrespective of the alkyl chain length of the cations. The average number of hydrogen bonds per cations inside the CNT was found to be higher for [OMIM][BF4] (1.01), which suggests that [OMIM]+ imidazolium rings to be concentrated at the center of the CNT, which favors hydrogen bond. The reported results show the diffusion coefficients of ions in confinement are much lower in comparison to the bulk region. The interaction energy between [OMIM][BF4] (-8.75 kcal.mol−1.ion−1) and CNT was found to be higher as compared to other ILs. The cations paralleling the CNT surface are thermodynamically significantly more stable because of the substantial interfacial π-π stacking interactions, as shown by a comparison with the calculated interaction energies between cations and the CNTs. Our simulation results provide a molecular-level understanding of the stabilization and dispersion of CNT bundles in ILs. [ABSTRACT FROM AUTHOR]

This study aims to cast light on the nature of hydrogen bonds and their cooperativity that exists in alcohol-water ( $ \textrm{ROH}{({{\textrm{H}_2}\textrm{O}})_\textrm{n}} $ ROH ( H 2 O ) n ) ( $ \textrm{R} = - \textrm{C}{\textrm{H}_3}\textrm{ }({ - \textrm{Me}}),\textrm{ } - \textrm{C}{\textrm{H}_2}\textrm{C}{\textrm{H}_3}\textrm{ }({ - \textrm{Et}}) $ R = − C H 3 (− Me) , − C H 2 C H 3 (− Et)) (n = 1–10) clusters using atoms in molecules (AIM) theory and symmetry-adapted perturbation theory (SAPT). The investigation of optimum structures suggests that alcohol ( $ \textrm{ROH} $ ROH ) forms two hydrogen bonds, one primary hydrogen bond $ ({\textrm{O} - \textrm{H} \cdot \cdot \cdot \textrm{O}}) $ (O − H ⋅ ⋅ ⋅ O) , and one secondary hydrogen bond $ ({\textrm{C} - \textrm{H} \cdot \cdot \cdot \textrm{O}}) $ (C − H ⋅ ⋅ ⋅ O) Two types of hydrogen bonds are addressed in these studies, where alcohol works as the hydrogen bond donor $ ({\textrm{ROH} \cdot \cdot \cdot \textrm{O}{\textrm{H}_2}}) $ (ROH ⋅ ⋅ ⋅ O H 2 ) and hydrogen bond acceptor $ ({\textrm{RHO} \cdot \cdot \cdot \textrm{HOH}}) $ (RHO ⋅ ⋅ ⋅ HOH). The AIM results reveal that $ \textrm{RHO} \cdot \cdot \cdot \textrm{HOH} $ RHO ⋅ ⋅ ⋅ HOH and $ \textrm{ROH} \cdot \cdot \cdot \textrm{O}{\textrm{H}_2} $ ROH ⋅ ⋅ ⋅ O H 2 hydrogen bonds are partially covalent. The SAPT study demonstrates that in all the clusters studied herein, the electrostatic interaction between alcohol and water is the main attractive force, and its contribution may be two times larger than the separate corresponding contributions from the dispersion and the induction terms. The electron density (ρ) at the bond critical point (BCP) is a suitable parameter to assess the strength of the interaction. The current study shows the strength and nature of $ \textrm{ROH} \cdot \cdot \cdot \textrm{O}{\textrm{H}_2} $ ROH ⋅ ⋅ ⋅ O H 2 and $ \textrm{RHO} \cdot \cdot \cdot \textrm{HOH} $ RHO ⋅ ⋅ ⋅ HOH hydrogen bond, and cooperative effect in ( $ \textrm{ROH}{({{\textrm{H}_2}\textrm{O}})_\textrm{n}} $ ROH ( H 2 O ) n ) ( $ \textrm{R} = - \textrm{C}{\textrm{H}_3}\textrm{ }({ - \textrm{Me}}),\textrm{ } - \textrm{C}{\textrm{H}_2}\textrm{C}{\textrm{H}_3}\textrm{ }({ - \textrm{Et}}) $ R = − C H 3 (− Me) , − C H 2 C H 3 (− Et).) (n = 1–10). [ABSTRACT FROM AUTHOR]

This study investigates the interaction between copper (Cu) and silver (Ag) clusters and graphene-based materials using molecular dynamics simulations. It focuses on how graphene oxidation and aminated polyethylene glycol (PEG-NH2) functionalization influence interaction strength and cluster dynamics. The analysis includes pristine graphene (PG), low-oxidized graphene oxide (GOL), and PEGylated graphene oxide (GO-PEG-NH2). The results reveal that clusters on PG exhibit high mobility, while GO-PEG-NH2 significantly restricts mobility due to strong interactions, as evidenced by highly negative interaction energies. GO-PEG-NH2 systems also display pronounced subdiffusive behavior (α < 1), indicating strong binding and constrained motion. These findings underscore the critical role of PEG-NH2 functionalization in controlling cluster diffusion, paving the way for innovative designs in biomedical and catalytic nanocarrier applications. [ABSTRACT FROM AUTHOR]

Starting from (p‐tolylsulfinyl)ferrocene (1), a mixture of the complete series [CpFe{C5H5–n(SOTol‐p)n}] (n = 2–4) (2–4) in all regioisomers was obtained. After chromatographic separation, crystals of 1,2‐bis[(4‐methylbenzene)sulfinyl]ferrocene, 2a, and 1,3‐bis[(4‐methylbenzene)sulfinyl]ferrocene, 2b, both [Fe(C5H5)(C19H17O2S2)], as well as of 1,2,3‐tris[(4‐methylbenzene)sulfinyl]ferrocene, [Fe(C5H5)(C26H23O3S3)], 3a, and 1,2,3,4‐tetrakis[(4‐methylbenzene)sulfinyl]ferrocene ethyl acetate 0.75‐solvate, [Fe(C5H5)(C33H29O4S4)]·0.75C4H8O2, 4, could be isolated. Their molecular and crystal structures are compared with each other and also with the so far unreported structures of related 1,2‐bis(phenylsulfanyl)ferrocene, [Fe(C5H5)(C17H13S2)], 5, and 1,2,3,4‐tetrakis(phenylsulfanyl)ferrocene, [Fe(C5H5)(C29H21S4)], 6. In all the sulfinyl structures, the O atoms of the S=O groups are in equatorial positions, except for that in tetrasubstituted 4. All the arene rings of these compounds (except for one ring in 4) are in axial positions directed away from the Fe atom, mostly in a near perpendicular orientation with respect to the plane of the cyclopentadienyl ring. The main intermolecular interactions in the crystals are C—H...H—C, C—H...π and C—H...O, while C—H...S interactions are much less important, except for tetrasulfanyl compound 6. π–π interactions (intramolecular) are only important in compound 3a. Hirshfeld analysis shows that dispersion terms are dominant for the interaction energies of all six compounds. In general, the calculated total interaction energies increase with increasing number of substituents and are higher for the sulfinyl than for the sulfanyl groups. [ABSTRACT FROM AUTHOR]

This work conducts a comprehensive theoretical study on the non‐covalent complexation between cyclocarbons and C60 fullerene for the first time. The binding energy between cyclocarbons and C60 fullerene is significantly stronger than that between two C18 or two C60 fullerenes, indicating a particularly strong affinity. The cyclocarbons and C60 fullerene can spontaneously assemble into complexes in the gas phase at room temperature, and the hydrophobic effect caused by the solvent environment can promote this binding. The binding strength with C60 fullerene increases almost linearly with the increase of cyclocarbon size, and the C34@C60 dimer exhibits a perfect nano‐Saturn structure. As the ring size increases, the angle between the two cyclocarbons of the 2 : 1 trimers formed by cyclocarbons and C60 fullerene gradually decreases. In C60@2 C34 trimer, the fullerene is symmetrically surrounded by two cyclocarbons. The results on the trimers formed by cyclocarbon and C60 fullerenes in a 1 : 2 ratio showed when the cyclocarbon sandwiched between two fullerenes is not quite large, the trimers exhibit an ideal dumbbell‐like structure, and the presence of the first fullerene has a significant synergistic effect on the binding of the second one. The cyclocarbon greatly promotes the dimerization of fullerenes, which acted as a "molecular glue". [ABSTRACT FROM AUTHOR]

To reveal the mechanism of interaction between styrene−butadiene rubber (SBR) modifier and asphalt components, the molecular dynamics (MD) method was used to study the diffusion behaviour at different temperatures. The diffusion behaviour was discussed using radial distribution function (RDF), mean square displacement (MSD), and relative concentration (RC). Interaction energy was used to verify the accuracy of the simulations. The simulated results indicate that the order of the four asphalt components prone to aggregation with SBR is as follows: saturated >aromatics >asphaltene >resins. The interaction between SBR modifier and asphalt components affects the diffusion of asphalt components. At 160°C, the distribution of components is the most uniform. When the temperature is too low or too high, the components dissociate from each other. The results of interaction energy are consistent with the conclusion. This study reveals the mechanism of component interaction of SBR modified asphalt. [ABSTRACT FROM AUTHOR]

Solid-state drug delivery systems for the drug substances transport are of great importance nowadays. In the present work, the non-covalent interactions between taxifolin (Tax) and graphene as well as nitrogenated (N-doped) graphenes were systematically studied by using a wide set of theoretical techniques. Symmetry-adapted perturbation theory (SAPT0) calculations confirmed more favorable adsorption of Tax on N-doped graphenes compared to pristine graphene. It was established that dispersion interactions play the main role in the attractive interactions (>60%), whereas electrostatic and induction forces contribute only moderately to the attraction (~25% and 7–8%, respectively). Independent gradient model (IGM) analysis visually demonstrated the existence of dispersion interactions and hydrogen bonding in the studied Tax complexes. Ab initio molecular dynamics calculations indicated stability of these complexes at different temperatures. Our results show that N-doped graphenes with the enhanced interaction energy (Eint) toward Tax are promising candidates for the technical realization of the targeted drug delivery systems. [ABSTRACT FROM AUTHOR]

Asphaltene deposition poses a significant threat to the safe production of crude oil as it tends to occur in forming porous media, wellbores, pipelines, and refining equipment. It is also responsible for the high viscosity of crude oil, making it challenging to recover heavy crude oil. This study investigates the impact of aliphatic chain length on asphaltene aggregation and the molecular properties of organic solvents and dispersants interacting with asphaltenes. To achieve this, two model asphaltenes, M1 and C5Pe, were used in molecular dynamics simulations using radial distribution function, root means square displacement, diffusion coefficient, solubility parameter, cohesion energy density, and interaction energy as characterization parameters. The simulations revealed that the aggregation onset of C5Pe and M1 occurs at 2–5 Å at room temperature and pressure, and π–π stacking is the primary mode of aggregation, with the presence of heteroatomic groups providing additional forces for stable aggregation. Additionally, it was found that the π–π interactions weakened with the increase of the side chain length. The study also investigated the molecular behavior of asphaltenes in six organic solvents and found that M1 was more soluble in aromatic solvents than C5Pe, and undesirable solvents could induce asphaltene aggregation. Furthermore, the effect of five dispersants on asphaltene aggregation was explored, with PIBSI, BEHP, B-DBSA, CTAB, and benzoic acid showing decreasing dispersing ability in that order at lower concentrations. However, at higher concentrations, the effect of some dispersants diminishes and triggers self-aggregation behavior. [ABSTRACT FROM AUTHOR]

The heat of mixing of some petrological relevant substitutions (i.e., Mg-Al, Si-Al, Mg-Ti, Mg-Ca, and Mg-Fe) was investigated systematically in silicates, titanates, tungstates, carbonates, oxides, hydroxides, and sulphates by density functional theory calculations (e.g., melilite, chlorite, biotite, brucite, cordierite, amphibole, talc, pseudobrookite, pyroxene, olivine, wadsleyite, ilmenite, MgWO4, ringwoodite (spinel), perovskite, pyrope-grossular, magnesite-calcite, MgO-CaO, anhydrous and different hydrated MgSO4). A specific substitution is characterised by different microscopic interaction energies in different minerals, e.g., the octahedral Mg-Al exchange on a single crystallographic site in pyroxene has a microscopic interaction energy that is more than twice compared to that in biotite. A comparative investigation of the heat of mixing using microscopic interaction energies on a single crystallographic site has the advantage that they are not influenced by cation ordering. They could be successfully correlated with the stiffnesses of the minerals, which in turn were scaled to the oxygen packing fraction, a parameter that is easily available for poorly investigated minerals. With this information, the interaction energies of a certain substitution can be transferred from minerals where they are well-known to mineral groups where they are less- or unknown. Using the cross-site terms and the microscopic interaction energies, the macroscopic interaction energies of the coupled substitution, e.g., Mg + Si = Al + Al, of biotite and pyroxene were calculated, which are, however, affected by cation ordering and different degrees of local charge balance, for which appropriate models are necessary. [ABSTRACT FROM AUTHOR]

To solve the problem of the oscillation stability of direct-driven wind-powered grid-connected systems with a low-voltage crossing control, a method of oscillation stability analysis for these systems, based on interactive energy, is proposed in this paper. Firstly, a dynamic energy model of a direct-driven wind-powered grid-connected system is established, considering a low-voltage traverse control. Secondly, the energy is divided into four parts—the line parameter energy, current inner loop energy, PLL energy, and current inner loop–PLL interaction energy—and the conduction path of the energy during a low-voltage crossing is described. On this basis, the aperiodic components of each energy path are analyzed, the stability level of the system is quantified, the influence of the different control parameters on the interactive energy dissipation is deduced, the key interactive control links affecting the stability of the system are screened, and the influence rules of the parameters are expounded. Finally, a direct-driven wind-powered grid-connected system model is built on the Rt-lab platform, and it is verified by a simulation test. The results show that the interaction energy generated by the interaction of the current inner loop and phase-locked loop is a key factor affecting the stability of the direct-driven wind-powered grid-connected system. The simulation test parameters of the control group were adjusted as the current inner loop's proportion parameter increased from 1.32 to 5.28, the current inner loop's integral parameter increased from 4.48 to 6.42, the PLL's proportion parameter decreased from 9.45 to 6.3, and the PLL's integral parameter decreased from 50.25 to 40.2. Both the theoretical and experimental results show that increasing the current inner loop's integral and proportion parameters can improve the stability level of the direct-driven wind-powered grid-connected system; reducing the phase-locked loop's proportion and integral parameters can also improve the stability level of the grid-connected system. [ABSTRACT FROM AUTHOR]

Determining binding affinities in protein–protein and protein–peptide complexes is a challenging task that directly impacts the development of peptide and protein pharmaceuticals. Although several models have been proposed to predict the value of the dissociation constant and the Gibbs free energy, they are currently not capable of making stable predictions with high accuracy, in particular for complexes consisting of more than two molecules. In this work, we present ProBAN, a new method for predicting binding affinity in protein–protein complexes based on a deep convolutional neural network. Prediction is carried out for the spatial structures of complexes, presented in the format of a 4D tensor, which includes information about the location of atoms and their abilities to participate in various types of interactions realized in protein–protein and protein–peptide complexes. The effectiveness of the model was assessed both on an internal test data set containing complexes consisting of three or more molecules, as well as on an external test for the PPI‐Affinity service. As a result, we managed to achieve the best prediction quality on these data sets among all the analyzed models: on the internal test, Pearson correlation R = 0.6, MAE = 1.60, on the external test, R = 0.55, MAE = 1.75. The open‐source code, the trained ProBAN model, and the collected dataset are freely available at the following link https://github.com/EABogdanova/ProBAN. [ABSTRACT FROM AUTHOR]

Studying how polycyclic aromatic hydrocarbons transform into soot particles provides insights into factors affecting their formation, composition, and size distribution. Understanding the growth mechanisms of soot from PAHs is crucial for combustion processes and energy efficiency, addressing environmental, health, and energy challenges linked to soot emissions and air pollution. This research aimed to deepen our understanding of these mechanisms by investigating them through molecular dynamics simulations. It used naphthalene as a representative polycyclic aromatic hydrocarbon. The study explored the effect of parameters like hydrogen atomic percentage and heat flux on properties, such as interaction energy, center of mass size, and soot mass size. Results show that increasing hydrogen atomic percentage from 5 % to 25 % increases the interaction energy from −0.15 to −0.12 kcal/mol. At the same time, it reduces the center of mass size from 92.31 to 88.27 Å and the soot mass size from 30.13 to 28.30 Å. Moreover, raising external heat flux from 0.01 to 0.05 W/m2 increases the interaction energy from −0.1 to −0.08 kcal/mol, but increases the center of mass size from 88.49 to 90.18 Å and soot mass size from 28.33 to 30.30 Å after 10 ns.

Abstract Expansive soils are known to be hazardous materials for infrastructure due to their high shrinking or swelling potential. Understanding the shrinking factors of expansive soils such as montmorillonite (MMT) is essential for predicting their mechanical properties. The interactions between the components of Na-MMT clays, e.g., MMT layer–layer (LL), layer–cation (LC), layer–water (LW) and water–cation (WC), are responsible for its shrinking behavior. In this study, molecular dynamics simulation and grand canonical Monte Carlo simulations are used to investigate the interaction energy evolution in the layered structure of Na-MMT for the shrinkage mechanisms analysis of clay. The results of simulation indicate that the magnitude of the interaction energy contributed by the interlayer cations dehydration is the driving force of the interlayer shrinkage. Furthermore, in the hydrated state, with one water layer, two water layers and three water layers, the attractive interactions between WC and LW, maintain the stability of the clay layers. However, at the dry state, the interaction energy between layers and cations appears to be the most essential component in holding the stacked layers together, which provides structural stability to the clay sheets. Finally, the study reveals that intermolecular interactions contribute to the mechanical properties of clays such as cohesive and elastic properties.

The benzene dimer (BD) is an archetypal model of π∙∙∙π and C–H∙∙∙π noncovalent interactions as they occur in its cofacial and perpendicular arrangements, respectively. The enthalpic stabilization of the related BD structures has been debated for a long time and is revisited here. The revisit is based on results of computations that apply the coupled-cluster theory with singles, doubles and perturbative triples [CCSD(T)] together with large basis sets and extrapolate results to the complete basis set (CBS) limit in order to accurately characterize the three most important stationary points of the intermolecular interaction energy (ΔE) surface of the BD, which correspond to the tilted T-shaped (TT), fully symmetric T-shaped (FT) and slipped-parallel (SP) structures. In the optimal geometries obtained by searching extensive sets of the CCSD(T)/CBS ΔE data of the TT, FT and SP arrangements, the resulting ΔE values were −11.84, −11.34 and −11.21 kJ/mol, respectively. The intrinsic strength of the intermolecular bonding in these configurations was evaluated by analyzing the distance dependence of the CCSD(T)/CBS ΔE data over wide ranges of intermonomer separations. In this way, regions of the relative distances that favor BD structures with either π∙∙∙π or C–H∙∙∙π interactions were found and discussed in a broader context. [ABSTRACT FROM AUTHOR]

A computational study on the host–guest complexes of neutral bis(4-nitrophenyl)squaramide (SQ) and halide anions is reported. In the gas-phase, the calculated interaction and stabilization energies indicates a diminishing intrinsic affinity of SQ for anions from fluoride to iodide. The nature of interactions is investigated using Natural Bond Orbital (NBO), Quantum Theory of Atoms in Molecules (QTAIM) along with Energy Decomposition Analysis-Natural Orbitals for Chemical Valence (EDA-NOCV). While electrostatic interactions account for roughly 60% of the total, EDA-NOCV analysis demonstrated increasing contributions of orbital interactions from SQ ⋯ I - to SQ ⋯ F - complexes. In solution, thermodynamic cycle analyses and Gibbs free energy calculations reveal a propensity towards the formation of SQ ⋯ F - , taking into account the influence of solvation energies on the overall stability. The consistent trend observed in selectivity both in the gas phase and in solution suggests that changes in solvation energy do not significantly impact the stability of complexes. The findings were additionally supported by a significant correlation observed between the computed and experimental formation constants. [ABSTRACT FROM AUTHOR]

Thermal recovery techniques for producing oil sands have substantial environmental impacts. Surfactants can efficiently improve thermal bitumen recovery and reduce the required amount of steam. Such a technique requires solid knowledge about the interaction mechanism between surfactants, bitumen, water, and rock at the nanoscale level. In particular, oil sands ores have extremely complex mineralogy as they contain many clay minerals (montmorillonite, illite, kaolinite). In this study, molecular dynamics simulation is carried out to elucidate the unclear mechanisms of clay minerals contributing to the bitumen recovery under a steameanionic surfactant co-injection process. We found that the clay content significantly influenced an oil detachment process from hydrophobic quartz surfaces. Results reveal that the presence of montmorillonite, illite, and the siloxane surface of kaolinite in nanopores can enhance the oil detachment process from the hydrophobic surfaces because surfactant molecules have a stronger tendency to interact with bitumen and quartz. Conversely, the gibbsite surfaces of kaolinite curb the oil detachment process. Through interaction energy analysis, the siloxane surfaces of kaolinite result in the most straightforward oil detachment process. In addition, we found that the clay type presented in nanopores affected the wettability of the quartz surfaces. The quartz surfaces associated with the gibbsite surfaces of kaolinite show the strongest hydrophilicity. By comparing previous experimental findings with the results of molecular dynamics (MD) simulations, we observed consistent wetting characteristics. This alignment serves to validate the reliability of the simulation outcomes. The outcome of this paper makes up for the lack of knowledge of a surfactant-assisted bitumen recovery process and provides insights for further in-situ bitumen production engineering designs. [ABSTRACT FROM AUTHOR]

When nano-fillers are used to enhance the thermal conductivity of organic phase change materials (PCMs), the naturally formed interface is considered to hinder thermal transport of the composite PCMs. However, the effect of the interface on the thermal properties of surrounding PCM has not been fully studied. In this paper, three composite PCMs (Ery@SiC, Ery@SiO2 and Ery@Si3N4) were prepared by melt-blending method. The local thermal conductivity and reduced Young's modulus (E⋆) of the erythritol at the interface and far away from the interface in the composite PCMs were simultaneously measured by scanning thermal microscopy (SThM). The results revealed significant enhancement in local thermal conductivity of erythritol at the interface and its obvious positive correlation with E⋆. For different composite PCMs, molecular dynamics (MD) simulations suggested that the increase in intrinsic thermal conductivity and E⋆ of erythritol is attributed to the increase in interaction energy between erythritol and nanoparticles, as more erythritol phonon vibrations transform from localized mode to delocalized mode and erythritol has a higher density at the interface. These findings will provide new ideas for the design of PCM for energy storage. [ABSTRACT FROM AUTHOR]

This study shows the exploration of the gas‐sensing capabilities of C6N8 material against toxic gases like phosphine (PH3) and phosphorous trichloride (PCl3). First‐principles study based on M05‐2X/LanL2DZ (d, p) method was performed to investigate the interaction energy (Eint.), frontier molecular orbitals (FMOs), natural bonding orbital (NBO), noncovalent interactions (NCIs), partial density of states (PDOS), molecular electrostatic potential (MEP), and quantum theory of atoms in molecules (QTAIM) analyses. The interaction energy results showed that PCl3@C6N8 (−23.45 kJ/mol) is more stable than PH3@C6N8 (−14.79 kJ/mol). A considerable decrease in the HOMO‐LUMO band gap of C6N8 was observed as a result of its complexation with the analytes. QTAIM and NCI analyses indicated the presence of weak noncovalent interactions between C6N8 and gases (PH3 and PCl3). SAPT0 analysis was performed to quantify the NCIs. MEP maps of complexes revealed the localization of electronic density on C6N8. The little recovery time of complexes (determined at 300 K) showed that C6N8 can serve as a reusable sensing material against PH3 and PCl3. Our results demonstrate that the C6N8 surface is a reliable material for detecting phosphine and phosphorous trichloride gases. [ABSTRACT FROM AUTHOR]

Polymers adsorb onto nanoparticles, NPs, by different mechanisms. Thus, they reduce coagulation, avoid undesired phase separation or clustering, and give rise to hybrid colloids. These find uses in many applications. In cases of noncovalent interactions, polymers adsorb onto nanoparticles, which protrude from their surface; the polymer in excess remains in the medium. In covalent mode, conversely, polymers form permanent links with functional groups facing outward from the NPs' surface. Polymers in contact with the solvent minimize attractive interactions among the NPs. Many contributions stabilize such adducts: the NP–polymer, polymer–polymer, and polymer–solvent interaction modes are the most relevant. Changes in the degrees of freedom of surface-bound polymer portions control the stability of the adducts they form with NPs. Wrapped, free, and protruding polymer parts favor depletion and control the adducts' properties if surface adsorption is undesired. The binding of surfactants onto NPs takes place too, but their stabilizing effect is much less effective than the one due to polymers. The underlying reason for this is that surfactants easily adsorb onto surfaces, but they desorb if the resulting adducts are not properly stabilized. Polymers interact with surfactants, both when the latter are in molecular or associated forms. The interactions occur between polymers and ionic surfactants or amphiphiles associated with vesicular entities. Hybrids obtained in these ways differ each from each other. The mechanisms governing hybrid formation are manifold and span from being purely electrostatic to other modes. The adducts that do form are quite diverse in their sizes, shapes, and features, and depend significantly on composition and mole ratios. Simple approaches clarify the interactions among different particle types that yield hybrids. [ABSTRACT FROM AUTHOR]

Binary liquid systems serve as valuable prototypes for comprehending biologically and chemically relevant properties of hydrogen bonds, revealing both noteworthy patterns and anomalies in their behaviour. Aniline, acetone and their binary mixtures with other liquids are used in various industrial processes, drug design, and as cleaning agents. This study is a molecular dynamics exploration of aniline and acetone binary mixture, over a concentration range of 9 : 1–1 : 9 for each component. The investigation includes employing techniques such as radial distribution function (RDF), coordination number calculation, hydrogen bond statistics, and graph theoretical analysis (GTA) through the NetworkX module in python, cluster analysis, Voronoi entropy calculation, interaction energy calculation and FTIR spectroscopy for all concentrations studied. The results uncover a compelling trend: a decrease in the number of hydrogen bonds as the concentration of acetone increases. Additionally, increased acetone concentration correlates positively with the breakdown of larger and more complex hydrogen‐bonded structures, indicating the formation of small hydrogen‐bond structures. [ABSTRACT FROM AUTHOR]

Using carbon-supported (M/C, M = Ag, MnO, MnO2, Mn3O4 and Pd) composite electrodes as the oxygen depolarized cathode (ODC) for chlor-alkali electrolysis, the energy consumption can be greatly reduced. However, the electrode stability and mass transfer process caused by the interaction between the ODC and the electrolyte solution are not very ideal, resulting in low efficiency of the electroreduction reaction, and its mechanism is still unclear. In this work, the interaction model of ORR of M/C electrodes in alkaline NaCl solution (ANS) were constructed, and MD simulation of the models were carried out. Based on the calculation and analysis of the interaction energy, diffusion coefficient and radial distribution function, the interaction law between the carbon-supported composite electrode and ANS was found out, and the interaction mechanism was revealed. The results showed that the interaction between O2 in ANS and different M/C electrodes is mutually attractive at 353 K, and the order is Ag/C > Pd/C > MnO/C > MnO2/C >Mn3O4/C. The change law of diffusion coefficients of O2 in different M/C composite electrode systems is consistent with that of the interaction energy, but the ANS is opposite. O2 molecule needs to break through the interaction between ANS and M/C composite electrode to interact with the composite electrode. The results of RDF illustrated that it is difficult for O2 molecule to bond with the active component M in different M/C electrodes in the short-range region, but they form non-bonding interaction in the remote region. On the other hand, ANS and the active component M of different M/C electrodes have bond interaction in the short-range region, and non-bond interaction is greater than bond interaction in the remote region. These results provide theoretical basis for further research and development of electrode materials in chlor-alkali electrolysis industry. [ABSTRACT FROM AUTHOR]