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Unlike one-dimensional polymers, the theoretical framework on the behaviors of two-dimensional (2D) polymers is far from completeness. In this study, we model single-layer flexible 2D polymers of different sizes and examine their scaling behaviors in solution, represented by Rg ∼ Lν, where Rg is the radius of gyration and L is the side length of a 2D polymer. We find that the scaling exponent ν is 0.96 for a good solvent and 0.64 for under poor solvent condition. Interestingly, we observe a previously unnoticed phenomenon: under intermediate solvent conditions, the 2D polymer folds to maintain a flat structure, and as L becomes larger, multiple folded structures emerge. We introduce a shape parameter Q to diagram the relationship of folded structures with the polymer size and solvent condition. Theoretically, we explain the folding transitions by the competition between bending and solvophobic free energies. [ABSTRACT FROM AUTHOR]

Gas-phase molecules are a promising platform to elucidate the mechanisms of action and scope of polaritons for optical control of chemistry. Polaritons arise from the strong coupling of a dipole-allowed molecular transition with the photonic mode of an optical cavity. There is mounting evidence of modified reactivity under polaritonic conditions; however, the complex condensed-phase environment of most experimental demonstrations impedes mechanistic understanding of this phenomenon. While the gas phase was the playground of early efforts in atomic cavity quantum electrodynamics, we have only recently demonstrated the formation of molecular polaritons under these conditions. Studying the reactivity of isolated gas-phase molecules under strong coupling would eliminate solvent interactions and enable quantum state resolution of reaction progress. In this Perspective, we contextualize recent gas-phase efforts in the field of polariton chemistry and offer a practical guide for experimental design moving forward. [ABSTRACT FROM AUTHOR]

Aqueous mixtures of deep eutectic solvents (DESs) have emerged as a subject of interest in recent years for their tailored physicochemical properties. However, a comprehensive understanding of water's multifaceted influence on the microscopic dynamics, including its impact on improved transport properties of the DES, remains elusive. Additionally, the diffusion mechanisms within DESs manifest heterogeneous behavior, intricately tied to the formation and dissociation kinetics of complexes and hydrogen bonds. Therefore, it is imperative to explore the intricate interplay between bond kinetics, diffusion mechanism, and dynamical heterogeneity. This work employs water as an agent to explore their relationships by studying various relaxation phenomena in a DES based on acetamide and lithium perchlorate over a wide range of water concentrations. Notably, acetamide exhibits Fickian yet non-Gaussian diffusion across all water concentrations with Fickian ( τ f ) and Gaussian ( τ g ) timescales following a power-law relationship, τ g ∝ τ f γ , γ ∼ 1.4. The strength of coupling between bond kinetics and different diffusion timescales is estimated through various power-law relationships. Notably, acetamide–water hydrogen bond lifetime is linked to diffusive timescales through a single power-law over the entire water concentration studied. However, the relationship between diffusive timescales and the lifetime of acetamide–lithium complexes shows a sharp transition in behavior at 20 wt. % water, reflecting a change from vehicular diffusion below this concentration to structural diffusion above it. Our findings emphasize the critical importance of understanding bond dynamics within DESs, as they closely correlate with and regulate the molecular diffusion processes within these systems. [ABSTRACT FROM AUTHOR]

The solvent effect on H-BEA catalyzed cyclohexanol dehydration was investigated in water, dioxane, and cyclohexanol. The dynamic evolution of the Brønsted acid site of zeolite and its interaction with reactant molecules in different solvents were explored with ab initio molecular dynamics simulations, providing reliable configuration sampling to obtain configurations at equilibrium. Solvent profoundly changes the adsorption as well as the dehydration reaction of cyclohexanol in H-BEA, where the reaction is determined to follow the E2 mechanism in water and dioxane but the E1 mechanism in cyclohexanol untill saturation uptake. Near saturation uptake, all three solvents significantly reduce the cyclohexanol dehydration rates in H-BEA. Cyclohexanol loading also dramatically affects the kinetics of the dehydration reaction, displaying an overall decreasing trend with a local minimum present at intermediate loading of 6 molecules per unit cell, which is a result of the entropic effect associated with greater freedom of motion of the transition state. Rigorous quantification of enthalpy and entropy contributions to cyclohexanol adsorption and activation shed light on the solvent effect of zeolite-catalyzed alcohol dehydration. [ABSTRACT FROM AUTHOR]

We discuss key parameters that affect the reliability of hybrid simulations in the aqueous phase based on an efficient multi-scale coarse-grained polarizable pseudo-particle approach, denoted as pppl, to model the solvent water, whereas solutes are modeled using an all atom polarizable force field. Among those parameters, the extension of the solvent domain (SD) at the solute vicinity (domain in which each solvent particle corresponds to a single water molecule) and the magnitude of solute/solvent short range polarization damping effects are shown to be pivotal to model NaCl salty aqueous solutions and the hydration of charged systems, such as the hydrophobic polyelectrolyte polymer that we have recently investigated [Masella et al., J. Chem. Phys. 155, 114903 (2021)]. Strong short range damping is pivotal to simulate aqueous salt NaCl solutions at moderate concentration (up to 1.0M). The SD extension (as well as short range damping) has a weak effect on the polymer conformation; however, it plays a pivotal role in computing accurate polymer/solvent interaction energies. As the pppl approach is up to two orders of magnitude computationally more efficient than all atom polarizable force field methods, our results show it to be an efficient alternative route to investigate the equilibrium properties of complex charged molecular systems in extended chemical environments. [ABSTRACT FROM AUTHOR]

The celebrated generalized Stokes law predicts that the velocity of a particle pulled through a liquid by an external force, Fex, is directly proportional to the force and inversely proportional to the friction ζ acted by the medium on the particle. We investigate the range of validity of the generalized Stokes law at molecular length scales by employing computer simulations to calculate friction by pulling a tagged particle with a constant force. We thus calculate friction for two model interaction potentials, Lennard-Jones and soft sphere, for several particle sizes, ranging from radius (a) smaller than the solvent particles to three times larger. We next obtain friction from diffusion (D) by using Einstein's relation between diffusion and friction ζ in an unperturbed liquid. We find a quantitative agreement between the two at a small-to-intermediate pulling force regime for all the sizes studied. The law does break down at a large pulling force beyond a threshold value. Importantly, the range of validity of Stokes' scheme to obtain friction increases substantially if we turn off the attractive part of the interaction potential. Additionally, we calculate the viscosity (η) of the unperturbed liquid and find a good agreement with the Stokes–Einstein relation ζ = Cηa for the viscosity dependence with a value of C close to 5 π, which is intermediate between the slip and stick boundary condition. [ABSTRACT FROM AUTHOR]

The multiparticle collision dynamics (MPCD) simulation method is an attractive technique for studying the effects of hydrodynamic interactions in colloidal suspensions because of its flexibility, computational efficiency, and ease of implementation. Here, we analyze an extension of the basic MPCD method in which colloidal particles are discretized with a surface mesh of sensor nodes/particles that interact with solvent particles (MPCD + Discrete Particle or MPCD + DP). We use several situations that have been described analytically to probe the impact of colloidal particle mesh resolution on the ability of the MPCD + DP method to resolve short-ranged hydrodynamic interactions, which are important in crowded suspensions and especially in self-assembling systems that create high volume fraction phases. Specifically, we consider (A) hard-sphere diffusion near a wall, (B) two-particle diffusion, (C) hard-sphere diffusion in crowded suspensions, and (D) the dynamics of aggregation in an attractive colloidal suspension. We show that in each case, the density of sensor nodes plays a significant role in the accuracy of the simulation and that a surprisingly high number of surface nodes are needed to fully capture hydrodynamic interactions. [ABSTRACT FROM AUTHOR]

Identifying the stable surface phases under a given electrochemical conditions serves as the basis for studying the atomistic mechanism of reactions at solid/water interfaces. In this work, we systematically compare the performance of the two main approaches that are used to capture the impact of an aqueous environment, implicit and explicit solvent, on surface energies and phase diagrams. As a model system, we consider the magnesium/water interface with (i) Ca substitution and (ii) proton and hydroxyl adsorption. We show that while the implicit solvent model is computationally very efficient, it suffers from two shortcomings. First, the choice of the implicit solvent parameters significantly influences the energy landscape in the vicinity of the surface. The default parameters benchmarked on solvation in water underestimate the energy of the dissolved Mg ion and lead to spontaneous dissolution of the surface atom, resulting in large differences in the surface energetics. Second, in systems containing a charged surface and a solvated ion, the implicit solvent model may not converge to the energetically stable ionic charge state but remain in a high-energy metastable configuration, representing the neutral charge state of the ion. When these two issues are addressed, surface phase diagrams that closely match the explicit water results can be obtained. This makes the implicit solvent model highly attractive as a computationally-efficient surrogate model to compute surface energies and phase diagrams. [ABSTRACT FROM AUTHOR]

The technological landscape for industrial processes handling asphaltene is evolving at a rapid pace due to the increase in the extraction of heavy crude oil. The main underlying challenges in this regard are the flow assurance, the recovery of the spent solvent, and the sophisticated extractor setup required to develop the process to an industrial scale. The number of studies focused on the handling of the asphaltene at the atomic and molecular scales is growing enormously in order to identify new sustainable solvents for the effective extraction of asphaltene from heavy crude oil or oil-bearing sands. This Perspective focuses on the importance of density functional theory and molecular dynamics simulations to explore the broader range of asphaltene inhibitors, e.g., nanoparticles, ionic liquids, and deep eutectic solvents, to prevent asphaltene precipitation. We provide a concise overview of the major accomplishments, analyze the aspects that require attention, and highlight the path-breaking studies having a significant impact on the process of chemical enhanced oil recovery from heavy crude oil reservoirs primarily based on atomistic and molecular simulations. [ABSTRACT FROM AUTHOR]

We theoretically investigate homogeneous crystal nucleation in a solution containing a solute and a volatile solvent. The solvent evaporates from the solution, thereby continuously increasing the concentration of the solute. We view it as an idealized model for the far-out-of-equilibrium conditions present during the liquid-state manufacturing of organic electronic devices. Our model is based on classical nucleation theory, taking the solvent to be a source of the transient conditions in which the solute drops out of the solution. Other than that, the solvent is not directly involved in the nucleation process itself. We approximately solve the kinetic master equations using a combination of Laplace transforms and singular perturbation theory, providing an analytical expression for the nucleation flux. Our results predict that (i) the nucleation flux lags slightly behind a commonly used quasi-steady-state approximation. This effect is governed by two counteracting effects originating from solvent evaporation: while a faster evaporation rate results in an increasingly larger influence of the lag time on the nucleation flux, this lag time itself is found to decrease with increasing evaporation rate. Moreover, we find that (ii) the nucleation flux and the quasi-steady-state nucleation flux are never identical, except trivially in the stationary limit, and (iii) the initial induction period of the nucleation flux, which we characterize as a generalized induction time, decreases weakly with the evaporation rate. This indicates that the relevant time scale for nucleation also decreases with an increasing evaporation rate. Our analytical theory compares favorably with results from a numerical evaluation of the governing kinetic equations. [ABSTRACT FROM AUTHOR]

The hydrophilic pore morphology and solvent diffusion within model (amphiphilic) polymer membranes are simulated by dissipative particle dynamics (DPD). The polymers are composed of a backbone of 18 covalently bonded A beads to which at regular intervals side chains are attached. The side chains are composed of linear Ap chains (i.e., –A1–A2...Ap) from which two branches, [AsC] and [ArC], split off (s ≤ r). C beads serve as functionalized hydrophilic pendent sites. The branch lengths (s + 1 and r + 1) are varied. Five repeat unit designs (with general formula A3[Ap[AsC][ArC]]) are considered: A2[A3C][A3C] (symmetric branching), A2[A2C][A4C], A2[AC][A5C], A2[C][A6C] (highly asymmetric branching), and A4[AC][A3C]. The distribution of water (W) and W diffusion through nanophase segregated hydrophilic pores is studied. For similar primary length p, an increase in side chain symmetry favors hydrophilic pore connectivity and long-range water transport. C beads located on the longer [ArC] branches reveal the highest C bead mobility and are more strongly associated with water than the C beads on the shorter [AsC] branches. The connectivity of hydrophilic (W and W + C) phases through mapped replica of selected snapshots obtained from Monte Carlo tracer diffusion simulations is in line with trends found from the W bead diffusivities during DPD simulations. The diffusive pathways for protons (H+) in proton exchange membranes and for hydronium (OH−) in anion exchange membranes are the same as for solvents. Therefore, control of the side chain architecture is an interesting design parameter for optimizing membrane conductivities. [ABSTRACT FROM AUTHOR]

Glass formation and reorientational motions are widespread but often-neglected features of deep eutectic solvents although both can be relevant for the technically important ionic conductivity at room temperature. Here, we investigate these properties for two mixtures of ethylene glycol and ZnCl2, which were recently considered superior electrolyte materials for application in zinc-ion batteries. For this purpose, we employed dielectric spectroscopy performed in a broad temperature range, extending from the supercooled state at low temperatures up to the liquid phase around room temperature and beyond. We find evidence for a relaxation process arising from dipolar reorientation dynamics, which reveals the clear signatures of glassy freezing. This freezing also governs the temperature dependence of the ionic dc conductivity. We compare the obtained results with those for deep eutectic solvents that are formed by the same hydrogen-bond donor, ethylene glycol, but by two different salts, choline chloride and lithium triflate. The four materials reveal significantly different ionic and reorientational dynamics. Moreover, we find varying degrees of decoupling of rotational dipolar and translational ionic motions, which can partly be described by a fractional Debye–Stokes–Einstein relation. The typical glass-forming properties of these solvents strongly affect their room-temperature conductivity. [ABSTRACT FROM AUTHOR]

Cytoskeletal gels are engineered prototypes that mimic the contractile behavior of a cell in vitro. They are composed of an active polymer matrix and a liquid solvent. Their contraction kinetics is governed by two dynamic phenomena: mechanotransduction (molecular motor activation) and solvent diffusion. In this paper, we solve the transient problem for the simple case of a thin gel slab in uniaxial contraction under two extreme conditions: motor-limited or slow motor (SM) activation regime, and diffusion-limited or fast motor (FM) activation regime. The former occurs when diffusion is much faster than mechanotransduction, while the latter occurs in the opposite case. We observe that in the SM regime, the contraction time scales as t / t 0 ∼ (λ / λ 0) − 3 , with t 0 being the nominal contraction time, and λ and λ 0 being the final and initial stretches of the slab. t 0 is proportional to 1 / w ˙ , where w ˙ is the average mechanical power generated by the molecular motors per unit reference (dry polymer) volume. In the FM regime, the contraction time scales as t / t 1 ∼ (1 − λ / λ 0) 2 , with t 1 being the nominal contraction time, here proportional to the ratio L 2 / D , where L is the reference (dry polymer) thickness, and D is the diffusivity of the solvent in the gel. The transition between the SM and FM regimes is defined by a characteristic power density w ˙ ∗ , where w ˙ ≪ w ˙ ∗ gives the SM regime and w ˙ ≫ w ˙ ∗ gives the FM regime. Intuitively, w ˙ ∗ is proportional to D / L 2 , where, at a given power density w ˙ , a thinner gel slab (smaller L) or including smaller solvent molecules (higher D) is more likely to be in the SM regime given that solvent diffusion will occur faster than motor activation. [ABSTRACT FROM AUTHOR]

Deep eutectic solvents (DESs) emerged as potential alternative solvent media in multiple areas, including biomolecular (cryo)preservation. Herein, we studied the stability of a small protein (ubiquitin) in water and a betaine-glycerol-water (B:G:W) (1:2:ζ; ζ = 0, 1, 2, 5, 10) DES, through molecular dynamics. An AMBER-based model that accurately describes the density and shear viscosity of the DES is proposed. We find that water molecules are largely trapped in the solvent, precluding the formation of a full hydration layer, seemingly opposite to osmolytes' preferential exclusion/preferential hydration mechanism. Although the protein is stable in the DES, structural fluctuations are largely suppressed and only recovered upon sufficient hydration. This is explained by a solvent-slaving mechanism where β-fluctuations are key, with the non-monotonic hydration of some amino acids with the water content providing an explanation to the non-monotonic folding of some proteins in aqueous DESs. A major thermal stability enhancement in the DES is also observed, caused by a similar slowdown of the backbone torsional dynamics. Our results support a kinetic stabilization of the protein in the DES, whereas a possible thermodynamic stabilization does not follow a preferential hydration or water entrapment mechanism. [ABSTRACT FROM AUTHOR]

For photosensitive polyurethane systems, reactive diluents are indispensable components whose main role is to reduce the viscosity of the polyurethane prepolymer to meet the requirements of the photocurable 3D printing technology for high fluidity of the precursor solution. Generally, the reactive diluent would be involved in the photocuring reaction, which in turn has a remarkable impact on the mechanical, reaction kinetics, and thermodynamic characteristics of the photosensitive polyurethane system. However, this feature is usually neglected in the study of photosensitive urethane acrylate (PUA) systems, so there is a considerable necessity to investigate the mechanism of active diluents in the photocured reaction of PUA systems. In this work, the effects of α-methyl groups along the chains of diluent molecules on the photoreaction kinetics, photocurable 3D printing, mechanical and mechanical properties, and thermodynamic characteristics of PUAs were investigated employing hydroxyethyl methacrylate and hydroxyethyl acrylate as active diluents, respectively. The relationship between chemical structure and kinetics of PUA systems was also elucidated by using dynamic mechanical analysis tests. The results demonstrated that the α-methyl group blocks the migration of reactive radicals, reduces the efficiency of the photoreaction, and causes an increase in the rigidity and strength of the molecular chain. This study not only revealed the effect of α-methyl on the kinetic mechanical and thermal performance of PUA systems but also paves the way for the development of a new class of photosensitive PUA materials used for the photocurable 3D printing technology. [ABSTRACT FROM AUTHOR]

The Adaptive Solvent-Scaling (AdSoS) scheme [J. Chem. Phys. 155 (2021) 094107] is an adaptive-resolution approach for performing simulations of a solute embedded in a fine-grained (FG) solvent region surrounded by a coarse-grained (CG) solvent region, with a continuous FG ↔ CG switching of the solvent resolution across a buffer layer. Instead of relying on a distinct CG solvent model, AdSoS is based on CG models defined by a dimensional scaling of the FG solvent by a factor s, accompanied by the s-dependent modulation of its mass and interaction parameters. The latter changes are designed to achieve an isomorphism between the dynamics of the FG and CG models, and to preserve the dispersive and dielectric solvation properties of the solvent with respect to a solute at FG resolution. As a result, the AdSoS scheme minimizes the thermodynamic mismatch between different regions of the adaptive-resolution system. The present article generalizes the scheme initially introduced for a pure atomic liquid in slab geometry to more practically relevant situations involving (i) a molecular dipolar solvent (e.g., water); (ii) a radial geometry (i.e., spherical rather than planar layers); and (iii) the inclusion of a solute (e.g., water molecule, dipeptide, ion, or ion pair). [ABSTRACT FROM AUTHOR]

We have studied diffusion and thermodiffusion in the ternary system polystyrene + toluene + cyclohexane over the entire composition range of the binary solvent toluene + cyclohexane and for polymer concentrations up to 0.1 mass fractions by multi-color optical beam deflection. The polystyrene molar masses were 4.88 and 17.90 kg/mol. The inversion problem of the contrast factor matrix could be avoided by reasonable a priori assumptions about the diffusion eigenvectors. The fast mode of the bimodal dynamics is attributed to the interdiffusion of the two solvents at constant polymer concentration, whereas the slow mode is due to the diffusion of the polymer with respect to the binary solvent. The amplitude of the fast mode vanishes in the pure toluene and the pure cyclohexane limits of the mixed solvent. The amplitude of the slow mode increases with polymer concentration. The composition and temperature dependence of the slow diffusion eigenvalue, the hydrodynamic correlation length, and the Soret coefficient of the polymer reflect the transition from a good to a theta solvent with increasing cyclohexane content and with decreasing temperature. Due to cross diffusion, cyclohexane reverses its migration direction between the fast and the slow mode, leading to a positive thermodiffusion but a negative Soret coefficient. The polymer thermodiffusion coefficients during the slow mode vary by approximately a factor of two, depending on the solvent composition. Rescaling with the solvent viscosity collapses all data onto a single master curve with an extrapolated value of ηDT ≈ 6 × 10−15 Pa m2 K−1 in the dilute limit. This value is well known from various other binary polymer/solvent mixtures. [ABSTRACT FROM AUTHOR]

Polariton chemistry may provide a new means to control molecular reactivity, permitting remote, reversible modification of reaction energetics, kinetics, and product yields. A considerable body of experimental and theoretical work has already demonstrated that strong coupling between a molecular vibrational mode and the confined electromagnetic field of an optical cavity can alter chemical reactivity without external illumination. However, the mechanisms underlying cavity-altered chemistry remain unclear in large part because the experimental systems examined previously are too complex for detailed analysis of their reaction dynamics. Here, we experimentally investigate photolysis-induced reactions of cyanide radicals with strongly-coupled chloroform (CHCl3) solvent molecules and examine the intracavity rates of photofragment recombination, solvent complexation, and hydrogen abstraction. We use a microfluidic optical cavity fitted with dichroic mirrors to facilitate vibrational strong coupling (VSC) of the C–H stretching mode of CHCl3 while simultaneously permitting optical access at visible wavelengths. Ultrafast transient absorption experiments performed with cavities tuned on- and off-resonance reveal that VSC of the CHCl3 C–H stretching transition does not significantly modify any measured rate constants, including those associated with the hydrogen abstraction reaction. This work represents, to the best of our knowledge, the first experimental study of an elementary bimolecular reaction under VSC. We discuss how the conspicuous absence of cavity-altered effects in this system may provide insights into the mechanisms of modified ground state reactivity under VSC and help bridge the divide between experimental results and theoretical predictions in vibrational polariton chemistry. [ABSTRACT FROM AUTHOR]

Absorption spectra of the solvatochromic dye 2,6-diphenyl-4-2,4,6-triphenyl-1-pyridinophenolate (B30) were measured in seven solvents of varying polarity over temperature ranging from each solvent's freezing point to 300 K. The excitation energies and their variances allowed calculations of the solvent reorganization energies, reorganization free energies and reorganization entropies as functions of temperature. The entropies of solvent packing around the chromophore are found to make major contributions to the reorganization free energies. The variances of the excitation energies depend only weakly on temperature, in disagreement with an expression that is often used for solvent reorganization free energies. Polar solvents reduce the transition dipole strength of B30's long-wavelength absorption band, probably because interactions with the solvent enhance the charge-transfer character of the transition. The dipole strength drops further at low temperatures. [ABSTRACT FROM AUTHOR]

Intramolecular electron transfer between two biphenyl groups linked by an androstane spacer and excitation of the pyridinium-N-phenolate betaine dye B30 to the first excited singlet state are studied by quantum/classical molecular-dynamics simulations at temperatures between 150 and 300 K in solvents with a range of polarities. Temperature dependences of the solvent reorganization energies, free energies, entropies, and the inhomogeneous broadening of B30's absorption band are examined. The variances of fluctuations of the energy gap between the reactant and product states do not have the direct proportionality to temperature that often is assumed to hold. An explanation for the observations is suggested. [ABSTRACT FROM AUTHOR]

The aluminum ion battery (AIB) is a promising technology, but there is a lack of understanding of the desired nature of the batteries' electrolytes. The ionic charge carriers in these batteries are not simply Al3+ ions but the anionic AlCl4− and Al2Cl7−, which form in the electrolyte. Using computational analysis, this study illustrates the effect of mole ratios and organic solvents to improve the AIB electrolytes. To this end, molecular dynamics simulations were conducted on varying ratios forming acidic, neutral, and basic mixtures of the AlCl3 salt with 1-ethyl-3-methylimidazolium chloride (EMImCl) ionic liquid (IL) and an organic solvent electrolyte [dichloromethane (DCM) or toluene]. The data obtained from diffusion calculations indicates that the solvents could improve the transport properties. Both DCM and toluene lead to higher diffusion coefficients, and higher conductivity. Detailed calculations demonstrated solvents can effectively improve the formation of AlCl3⋯Cl (AlCl4−) and AlCl4−···AlCl4− (Al2Cl7−) especially in acidic mixtures. The densities, around 1.25 g/cm3 for electrolyte mixtures of AlCl3-EMImCl, were consistent with experiment. These results, in agreement with experimental findings, strongly suggest that DCM in acidic media with AlCl3 and EMImCl might provide a promising basis for battery development. [ABSTRACT FROM AUTHOR]

How to fabricate perpendicularly oriented domains (PODs) of lamellar and cylinder phases in block copolymer thin films remains a major challenge. In this work, via a coarse-grained molecular dynamics simulation study, we report a solvent evaporation strategy starting from a mixed solution of A-b-B-type diblock copolymers (DBCs) and single-chain nanoparticles (SCNPs) with the same composition, which is capable of spontaneously generating PODs in drying DBC films induced by the interface segregation of SCNPs. The latter occurs at both the free surface and substrate and, consequently, neutralizes the interface selectivity of distinct blocks in DBCs, leading to spontaneous formation of PODs at both interfaces. The interface segregation of SCNPs is related to the weak solvophilicity of the internal cross-linker units. A mean-field theory calculation demonstrates that the increase in the chemical potential of SCNPs in the bulk region drives their interface segregation along with solvent evaporation. We believe that such a strategy can be useful in regulating the PODs of DBC films in practical applications. [ABSTRACT FROM AUTHOR]

Herein, we report the first example of Rh-catalyzed C(sp²)-H difluoroallylation of α,β-unsaturated amides with 3-bromo-3, 3-difluoropropene under mild conditions. The features of this protocol for difluoroallylation are unprecedented vinylic substrates, ethanol as a green solvent, good functional group and air compatibility, and scale-up synthesis with low catalyst loading. [ABSTRACT FROM AUTHOR]

A new substituted Hqnal ligand, Hqnal-5-Brq, and four resulting FeIII complexes [Fe(qnal-5-Brq)2]A·sol (A = NO3−, sol = CH3OH 1; A = ClO4−, sol = CH3OH 2; A = OTf−, sol = 2CH3OH·H2O 3; and A = NTf2−, sol = CH2Cl24; Hqnal-5-Brq = N-(5-bromo-8-quinolinyl)-2-hydroxynaphthaldimine), have been synthesized and characterized. All four complexes, despite having different anions, adopt similar 1D [Fe(qnal-5-Brq)2]+ cation chains linked by orthogonal π⋯π interactions. These chains are further connected to form 2D and 3D structures by other supramolecular interactions. Complexes 1–3 all exhibit abrupt spin crossover behaviors, with the transition temperatures being 230, 189, and 185 K, respectively, while complex 4 is in a high-spin state. The influence of solvents on spin crossover properties was assessed via magnetic measurements on the desolvated samples. Following desolvation, while complexes 1 and 2 show slight variations in their transition temperatures, complexes 3 and 4 undergo significant changes in their magnetic profiles. Desolvation in complex 3 leads to either a HS state or a very incomplete hysteretic transition with a low transition temperature for different sample batches. In contrast, the gradual desolvation in complex 4 leads to diminished solvent residues and progressive transition from a stable HS state to an SCO-active state. [ABSTRACT FROM AUTHOR]

A methodology was developed for synthesizing N -acyl- N '-sulfonyl hydrazides through acyl substitution reactions between activated amides and arylsulfonyl hydrazides. Optimization of the reaction conditions revealed that using Cs₂CO₃ as a base and 1,4-dioxane as a solvent at 25 °C for 12 hours produced the highest yields. Among various amides tested, N -benzoylsuccinimide was found to be the most reactive, with reduced reactivity observed for N -mesityl-, N -tosyl-, and N -Boc-substituted tertiary benzoyl amides. Cross-reactions between a diverse range of N -benzoylsuccinimides and arylsulfonyl hydrazides successfully produced the corresponding N -acyl- N′ -sulfonyl hydrazides with yields ranging from 63% to 94%. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Poly‐NHC‐based organometallic assemblies 3‐PF6, 3‐SbF6 and 3‐OTf were obtained and verified by NMR spectroscopy, ESI mass spectrometry and single‐crystal X‐ray diffraction analyses. Controllable structural interconversion was observed between the poly‐NHC‐based organometallic assemblies and their self‐aggregated dimers in solution affected by concentration, solvent and metal ion. 1H NMR spectra of assembly 3‐PF6 in CD3CN at different concentrations demonstrated controllable structural interconversion, and 19F NMR spectrum of assembly 3‐PF6 at high concentration further evidenced the presence of the free hexafluorophosphate anion and encapsulated hexafluorophosphate anion for its two sets of signals. In addition, single‐crystal X‐ray diffraction analysis provided clear evidence that in the solid state, two assemblies 3‐PF6 were vertically stuck, forming a self‐aggregated dimer with an encapsulated hexafluorophosphate anion. Investigating the reversible structural interconversion is beneficial for revealing the intrinsic nature on the atom level and paving the way to design the stimuli‐responsive functional system. [ABSTRACT FROM AUTHOR]

A sensitive, rapid, efficient, inexpensive, and easy-to-use vortex-assisted eutectic solvent microextraction process was extended to quantify Ponceau-4R (PN4R) in beverage samples followed by spectrophotometric detection. Here, a green solvent consisting of tetrabutylammonium bromide: n-octanol at a ratio of 1:3 was tested in the PN4R microextraction process. Also, different parameters affecting PN4R quantification through deep eutectic solvent in the microextraction model, including microliter volumes of extraction solvent, concentration of salt, extraction time, and pH were studied using multivariate procedures. Using this model, the maximum response was achieved with a eutectic solvent volume of 262 μL, extraction time of 5.3 min, pH 6.7, and 0.9% salt with Desirability = 1. The linear range was determined in optimum conditions to be from 15 to 1200 μg L−1. The enrichment factor and limit of detection were achieved to be 50-fold and 4.5 μg L−1, respectively. The limit of quantitation was 15 μg L−1. To monitor PN4R, this model has been used in fruit juice samples with favorable recoveries in the range of 97.8%–101%. [ABSTRACT FROM AUTHOR]

A simple, straightforward, and highly efficient greener approach for synthesizing bis(6‐aminouracil‐5‐yl)methane derivatives was developed by employing β‐cyclodextrin‐SO3H as supramolecular catalyst in water at 100 °C. A total of 16 bis(6‐aminouracil‐5‐yl)methanes were synthesized via a one‐pot reaction between substituted aromatic aldehydes, 6‐amino‐1,3‐dimethyluracil, and 10% β‐cyclodextrin‐SO3H in water with 84%–92% yield within 20–120 min. The salient features of this protocol included water as green solvent, β‐cyclodextrin‐SO3H as recyclable supramolecular catalyst, mild reaction conditions, easy isolation of pure products, and good to excellent yields. [ABSTRACT FROM AUTHOR]

We report a study of solvent effects on the rate, selectivity, and mechanism of (hetero)aryl (pseudo)halide oxidative addition to Pd(PCy3)2 as an exemplar of L2Pd(0) species. First, 2‐chloro‐3‐aminopyridine is observed to undergo faster oxidative addition in toluene compared to more polar solvents, which is not consistent with the trend we observe with many other 2‐halopyridines. We attribute this to solvent basicity hydrogen bonding between solvent and substrate. Greater hydrogen bond donation from the substrate leads to a more electron‐rich aromatic system, and therefore slower oxidative addition. We demonstrate how this affects rate and site‐selectivity for hydrogen bond donating substrates. Second, electron‐deficient multihalogenated pyridines exhibit improved site‐selectivity in polar solvents, which we attribute to different C−X sites undergoing oxidative addition by two different mechanisms. The C−X site that favours the more polar nucleophilic displacement transition state is preferred over the site that favours a less‐polar 3‐centered transition state. Finally, (hetero)aryl triflates consistently undergo faster oxidative addition in more polar solvents, which we attribute to highly polar nucleophilic displacement transition states. This leads to improved site‐selectivity for C−OTf oxidative addition, even in the presence of highly reactive 2‐pyridyl halides. [ABSTRACT FROM AUTHOR]

Introduction: Deep eutectic solvents (DESs) have emerged as green solvents with versatile applications, demonstrating significant potential in biocatalysis. They often increase the solubility of poorly water-soluble substrates, serve as smart co-substrates, modulate enzyme stereoselectivity, and potentially improve enzyme activity and stability. Despite these advantages, screening for an optimal DES and determining the appropriate water content for a given biocatalytic reaction remains a complex and time-consuming process, posing a significant challenge. Methods: This paper discusses the rational design of DES tailored to a given biocatalytic system through a combination of experimental screening and computational tools, guided by performance targets defined by solvent properties and process constraints. The efficacy of this approach is demonstrated by the reduction of CO2 to formate catalyzed by NADH-dependent formate dehydrogenase (FDH). By systematically analyzing FDH activity and stability, NADH stability (both long-term and short-term stability after solvent saturation with CO2), and CO2 solubility in initially selected glycerol-based DESs, we were able to skillfully guide the DES screening process. Results and discussion: Considering trade-offs between experimentally determined performance metrics of DESs, 20% solution of choline chloride:glycerol in phosphate buffer (ChCl:Gly80%B) was identified as the most promising solvent system for a given reaction. Using ChCl:Gly as a co-solvent resulted in an almost 15-fold increase in FDH half-life compared to the reference buffer and stabilized the coenzyme after the addition of CO2. Moreover, the 20% addition of ChCl:Gly to the buffer improved the volumetric productivity of FDH-catalyzed CO2 reduction in a batch system compared to the reference buffer. The exceptional stability of the enzyme in this co-solvent system shows great potential for application in continuous operation, which can significantly improve process productivity. Additionally, based on easily measurable physicochemical solvent properties and molecular descriptors derived from COSMO-RS, QSAR models were developed, which successfully predicted enzyme activity and stability, as well as coenzyme stability in selected solvent systems with DESs. [ABSTRACT FROM AUTHOR]

Grafting organophosphonic acids (PAs) on metal oxides has shown to be a flexible technology to tune the surface properties of metal oxides for various applications. The solvents applied in the commonly used synthesis method have associated impeding effect on tailoring the resulting modification degree. In this work, an alternative solid-phase manual grinding method is proposed that (i) is straightforward, (ii) can achieve controllable and higher modification degree, and (iii) excludes the use of solvent during the synthesis. Specifically, propylphosphonic acid (3PA) was grafted onto titania by manual grinding, and different modification degrees were obtained by varying the duration of the post-synthetic thermal treatment. Importantly, the solid-phase method can achieve a modification degree that is 25.0% higher than the maximal modification degree reached by the liquid-phase method, while its atom utilization efficiency is 4.8 times (toluene-based) or 7.5 times (water-based) that of the liquid-phase method. [ABSTRACT FROM AUTHOR]

A metal-free B(C6F5)3 and HFIP synergistically catalyzed bisarylation reaction between difluoroacetaldehyde ethyl hemiacetal and anilines was developed to efficiently synthesize symmetrical and unsymmetrical difluoromethylated diarylmethanes without using stoichiometric activating agents or in concentrated strong acid media. This efficient, scalable and operationally simple protocol displays high atom economy and broad substrate tolerance, allowing quick access to diverse symmetrical and unsymmetrical difluoromethylated diarylmethane products under mild conditions. Furthermore, the recyclability and reusability of the HFIP solvent make the reaction environmentally friendly. [ABSTRACT FROM AUTHOR]

A visible-light-initiated electron-donor–acceptor (EDA) complex-driven regioselective vicinal and oxidative geminal thiosulfonylation of alkynes is presented. Organic thiosulfonates act as an acceptor, producing either sulfonyl (RSO2˙) or thiyl (RS˙) radicals under base and solvent switchable conditions. Simultaneous installation of three different functionalities, viz carbonyl, sulfonyl, and thiyl, takes place under one condition, while another condition leads to vicinal thiolation and sulfonylation. [ABSTRACT FROM AUTHOR]

In this work, we explored the L -sodium ascorbate-promoted Cu(OTf)2-catalyzed hydrodehalogenation of o-halopicolinanilides in water for the first time. The catalytic system could regioselectively dehalogenate 2-Br/I of picolinanilides and features a ligand-free and green solvent. [ABSTRACT FROM AUTHOR]

ABSTRACT A chemically cross‐linked version of polystyrene is presented here that allows the preparation of reversibly mechanically compressible gels as NMR weakly aligning media. The gels can be successfully swollen in aromatic solvents such as toluene‐d8 and pyridine‐d5, as well as in CDCl3, and provided accurate measurements of 1DCH RDCs and 13C‐RCSAs. [ABSTRACT FROM AUTHOR]

Solvent competition for London dispersion attenuates its energetic significance in molecular recognition processes. By varying both the stacked contact area and the solvent, here we experimentally deconvolute solvent attenuation using molecular balances. Experimental stacking energies (phenyl to pyrene) correlated strongly with calculations only when dispersion was considered. Such calculations favoured stacking by up to −27 kJ mol−1 in the gas phase, but it was weakly disfavoured in our solution‐phase experiments (+0.5 to +4.6 kJ mol−1). Nonetheless, the propensity for stacking increased with contact area and in solvents with lower bulk polarisabilities that compete less for dispersion. Experimental stacking energies per unit change in solvent accessible area ranged from −0.02 kJ mol−1 Å−2 in CS2, to −0.05 kJ mol−1 Å−2 in CD2Cl2, but were dwarfed by the calculated gas‐phase energy of −0.6 kJ mol−1 Å−2. The results underscore the challenge facing the exploitation of dispersion in solution. Solvent competition strongly but imperfectly cancels dispersion at molecular recognition interfaces, making the energetic benefits difficult to realise. [ABSTRACT FROM AUTHOR]

Solvent competition for London dispersion attenuates its energetic significance in molecular recognition processes. By varying both the stacked contact area and the solvent, here we experimentally deconvolute solvent attenuation using molecular balances. Experimental stacking energies (phenyl to pyrene) correlated strongly with calculations only when dispersion was considered. Such calculations favoured stacking by up to −27 kJ mol−1 in the gas phase, but it was weakly disfavoured in our solution‐phase experiments (+0.5 to +4.6 kJ mol−1). Nonetheless, the propensity for stacking increased with contact area and in solvents with lower bulk polarisabilities that compete less for dispersion. Experimental stacking energies per unit change in solvent accessible area ranged from −0.02 kJ mol−1 Å−2 in CS2, to −0.05 kJ mol−1 Å−2 in CD2Cl2, but were dwarfed by the calculated gas‐phase energy of −0.6 kJ mol−1 Å−2. The results underscore the challenge facing the exploitation of dispersion in solution. Solvent competition strongly but imperfectly cancels dispersion at molecular recognition interfaces, making the energetic benefits difficult to realise. [ABSTRACT FROM AUTHOR]

A new approach to managing the extraction properties of eutectic solvents based on aliphatic alcohols is proposed. Aliphatic alcohols, when functioning as hydrogen bond donors within a eutectic solvent, significantly enhance the solvent's efficiency in extracting metal ions. Conversely, when the alcohol acts as a hydrogen bond acceptor, its extraction properties diminish. Molecular modelling reveals that the extraction efficiency of these alcohols is directly proportional to the intermolecular interaction energy between the components of the eutectic solvent. [ABSTRACT FROM AUTHOR]

For protein crystals in which more than two thirds of the volume is occupied by solvent, the featureless nature of the solvent region often generates a constraint that is powerful enough to allow direct phasing of X‐ray diffraction data. Practical implementation relies on the use of iterative projection algorithms with good global convergence properties to solve the difficult nonconvex phase‐retrieval problem. In this paper, some aspects of phase retrieval using iterative projection algorithms are systematically explored, where the diffraction data and density‐value distributions in the protein and solvent regions provide the sole constraints. The analysis is based on the addition of random error to the phases of previously determined protein crystal structures, followed by evaluation of the ability to recover the correct phase set as the distance from the solution increases. The properties of the difference‐map (DM), relaxed–reflect–reflect (RRR) and relaxed averaged alternating reflectors (RAAR) algorithms are compared. All of these algorithms prove to be effective for crystallographic phase retrieval, and the useful ranges of the adjustable parameter which controls their behavior are established. When these algorithms converge to the solution, the algorithm trajectory becomes stationary; however, the density function continues to fluctuate significantly around its mean position. It is shown that averaging over the algorithm trajectory in the stationary region, following convergence, improves the density estimate, with this procedure outperforming previous approaches for phase or density refinement. [ABSTRACT FROM AUTHOR]

Electrospun polystyrene (PS) fibers are produced using a mixed solvent of chloroform and n,n‐dimethylformamide (DMF) to investigate the influence of the solvent ratio on the fiber surface morphology and contact angle of the obtained mats. Electrospinning is a simple processing technique for producing fibers with diameters in the range of nanometers to a few micrometers. When using the different solvent ratios for this process, porous PS membranes are created due to nonsolvent and thermally induced phase separation (N‐TIPS). The morphology of the fibers is analyzed through scanning electron microscopy (SEM), which showed that fibers have diameters between 200 nm and 6 µm. SEM also revealed that the pores present on the surface of the fibers vary from densely compacted and well‐formed nanopores with diameters in the range of 20–50 nm to larger pores with sizes of ≈100–200 nm. The pore size varied with different solvent ratios. The surface area is analyzed using the Brunauer–Emmett–Teller (BET) method and found that the polymeric fibers have a high surface area (≈35 m2 g−1). The fibers with such morphology are highly hydrophobic, with a contact angle higher than 143°. These materials are excellent candidates for applications in textiles, filtration, and biomedical fields. [ABSTRACT FROM AUTHOR]

The Bucherer–Bergs multicomponent synthesis of hydantoins has been meticulously examined using density functional theory (DFT) at the B3LYP/6-311G level to scrutinise the reaction mechanism in diethyl ether as a solvent. This study explores all plausible pathways, optimises the structures of intermediates, and identifies corresponding transition states. Furthermore, a comprehensive computational analysis of molecular structures and their energy-structural correlations has been conducted. [ABSTRACT FROM AUTHOR]

Many studies of azobenzene photoswitches are carried out in polar aprotic solvents as a first principles characterization of thermal isomerization. Among the most convenient polar aprotic solvents are chlorinated hydrocarbons, such as DCM. However, studies of azobenzene thermal isomerization in such solvents have led to spurious, inconclusive, and irreproducible results, even when scrupulously cleaned and dried, a phenomenon not well understood. We present the results of a comprehensive investigation into the root cause of this problem. We explain how irradiation of an azopyridine photoswitch with UV in DCM acts not just as a trigger for photoisomerization, but protonation of the pyridine moiety through photodecomposition of the solvent. Protonation markedly accelerates the thermal isomerization rate, and DFT calculations demonstrate that the singlet-triplet rotation mechanism assumed for many azo photoswitches is surprisingly abolished. This study implies exploitative advantages of photolytically-generated protons and finally explains the warning against using chlorinated solvent with UV irradiation in isomerization experiments. Azobenzenes undergo reversible light-induced photoisomerization, resulting in marked spectroscopic, electronic, and mechanical changes, but their sensitivity towards solvents is not fully understood. Here, the authors report how irradiation of an azopyridine photoswitch with UV light in dichloromethane triggers protonation of the pyridine moiety through photodecomposition of the solvent, consequently accelerating thermal back isomerization and abolishing singlet-triplet rotation mechanisms. [ABSTRACT FROM AUTHOR]

Developing multicomponent reactions in a cascade manner is a long-standing interest to chemists to access valuable organic materials more economically. Herein, we described a simple, economically viable method for synthesizing 11H-benzo[b]fluoren-11-one, a dual-state organic fluorophore, starting from ortho phthalaldehyde (OPA) in DMSO solvent. Simple and rapid product isolation, high atom economy, short reaction time, and scalability are the attractive features of the method. During the optimization of the reaction condition, we observed that DMSO, DMF, and acetone served one carbon to form the said compound besides their role as solvents. A plausible mechanism has been proposed based on the evidence obtained from LCMS analysis of the incomplete reaction mixture. [ABSTRACT FROM AUTHOR]

With the drive toward the development of large‐area organic solar cells (OSCs), there is a critical need for advanced fabrication techniques that ensure both their efficiency and scalability. In particular, a shift from toxic halogenated solvents to safer non‐halogenated alternatives such as o‐xylene, which have lower environmental and health impacts, is required. However, transitioning to non‐halogenated solvents can lead to serious problems, including aggregation within the active layer, which compromises film morphology and the resulting efficiency of OSCs. To address this aggregation, in the present study, the 2‐ethylhexyl (EH) groups in L8‐BO(EH‐EH) are replaced with longer chains (2‐heptylundecyl [HU], 2‐decyltetradecyl [DT], and 2‐dodecylhexadecyl [DH] groups) to synthesize the non‐fullerene acceptors (NFAs) of L8‐BO(HU‐HU), L8‐BO(HU‐DT), and L8‐BO(HU‐DH). The NFAs with the longer alkyl chains are highly soluble in o‐xylene and produce highly uniform films, making them more suitable for use in large‐area OSCs. Using the NFAs, slot‐die‐coated organic solar modules with an active area of 200 cm2 are fabricated; the L8‐BO(HU‐DT)‐based module exhibits an impressive power conversion efficiency of 11.44%. This work thus underscores the asymmetrical elongation of alkyl chains in the NFAs to mitigate severe NFA phase separation and improve film printability in the practical production of organic solar modules. [ABSTRACT FROM AUTHOR]

Lubricant‐infused organo‐gels with low surface energy solvents represent an environment‐friendly lubricating material, while the poor mechanical performance incapacitates them to harsh and intricate service conditions. To address this challenge, a simple yet highly effective strategy to prepare strong, smart, and slippery organo‐gels by glassifying the polymer network is reported. As a proof of concept, appropriate amounts of rigid solvophobic poly(phenyl methacrylate) (PPMA) units are integrated into a solvophilic poly(cyclohexyl acrylate) (PCHA) network infiltrated with lubricant. Upon forming bicontinuous phase‐separated structures, the rigid solvent‐free PPMA segments stay in glassy states, serving as a load‐bearing phase to toughen the materials effectively. Meanwhile, the soft PCHA phase maintains lubricity and extensibility by holding a substantial amount of lubricant. Owing to the synergistic effect, the gels manifest glass‐like mechanical performance with high rigidity (46.6 MPa), strength (7.7 MPa), and toughness (23.7 kJ m−2). Moreover, the materials exhibit high thermo‐sensitivity with the elastic modulus reversibly decreasing from 46.6 MPa at 20 °C to 0.23 MPa at 50 °C, endowing the gels with shape‐memory properties. Furthermore, the organo‐gels display satisfactory anti‐adhesiveness to various foreign matters. Taken together, the work represents a facile and universal strategy to reinforce organo‐gels, thereby adapting them to various applications. [ABSTRACT FROM AUTHOR]

Herein, we disclose the hitherto unknown cross-conjugated vinylogous annulation of π-CF3-allyl Pd complexes with 4-methyl-3-trifluoroacetyl-quinolones to access phenanthridones. The CF3 group in the Pd-π-allyl complex is key for exclusive γ-regioselectivity and further annulation. The solvent switch orchestrates the dihydro-phenanthridones (CH3CN) and hydroxy-phenanthridones (DMF) in good yields, and also showed excellent optoelectronic properties. [ABSTRACT FROM AUTHOR]

The transformation of alcohols to important classes of compounds is a central topic in chemistry because they are abundant, renewable, and attractive building blocks. The alkali‐mediated/catalyzed borrowing hydrogen and aerobic dehydrogenation processes of alcohols open a new and sustainable access for the alcohol conversion under transition‐metal‐free conditions. In this review, we summarize the recent alkali‐mediated/catalyzed sequential reactions involving the borrowing hydrogen and aerobic dehydrogenation processes of alcohols. Furthermore, this review not only introduces the tentative pathways of these transformations, but also discusses the role of alkali, solvent effects, and substrate reactivity on these reactions. [ABSTRACT FROM AUTHOR]

Organic solar cells (OSCs) have emerged as promising candidates for renewable energy harvesting due to their lightweight, flexible, and low‐cost fabrication potential. The efficiency of OSCs is largely determined by the choice of solvents, which significantly affect the film morphology of the active layers, the intermixed donor‐acceptor domains, and overall device performance. Beginning with an introduction to the importance of solvent selection, the screening and classification of solvents, emphasizing their characteristics and classification based on sustainability, solubility, and other additional considerations are explored. Various non‐halogenated solvents, highlighting commonly used aromatic solvents, biomass‐derived solvents, and water/alcohol‐based solvents are explored. The state‐of‐the‐art donor and acceptor materials, focusing on efficient donor materials such as PM6 and D18, and high‐performing Y‐series acceptors are also presented. Strategies for developing high‐performance OSCs processed using non‐halogenated solvents are examined, including solvent engineering with additive and additive‐free approaches, ternary strategies, and layer‐by‐layer techniques. The fabrication of large‐area devices using non‐halogenated solvents is addressed, focusing on blade‐coating, slot‐coating, and other processing techniques. Finally, this review outlines future research directions in the non‐halogenated solvent processing of OSCs, emphasizing the need for continuous innovation to overcome existing limitations and propel OSC technology toward commercial viability. [ABSTRACT FROM AUTHOR]

A simple and sustainable propylphosphonic anhydride (T3P)-assisted methodology for the synthesis of N-acyl tryptamines, an interesting class of gut microbiota-derived endocannabinoid-like lipid mediators, was proposed. This protocol is characterized by great operational simplicity, and all products were obtained at room temperature, without the use of an inert atmosphere and by using limited amounts of non-halogenated solvents. Finally, the possibility to realize the reaction under mechanochemical conditions was explored with interesting results. [ABSTRACT FROM AUTHOR]