Artigos de revistas: "Solvations"

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Kazbekovna Kuizheva, Saida, Ludmila Grigorievna Matveeva, Tatiana Anatolievna Ovsyannikova, Vladimir Ivanovich Zarubin e Anastasiy Valerievna Kaplina. "Circular business paradigm in innovative solvations of industrial ecosystems of regions". Nexo Revista Científica 35, n.º 01 (5 de abril de 2022): 199–211. http://dx.doi.org/10.5377/nexo.v35i01.13931.

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In the conditions of the continuing crisis, determined both by external sanctions against Russia from several Western states, and the ongoing coronavirus pandemic, it is the industrial ecosystems of the country's regions that form innovative solvations with subjects of other industries and spheres of activity and are the main rational consumers of regional resources that combine the potential of innovative speed, high quality, adaptation to changing consumer demands, etc. This article examines the scientific and practical problem of the formation and functioning of innovation-oriented industrial solvates, the solution of which is in line with the new approach proposed by the authors to identify, determine the sources and rank the effects of innovative solvations in the regional industry. This approach is built on the concept of a circular economy, which is based on the assumption of the most rational organization and use of all types of resources of integrated industrial enterprises and related industries (spheres of activity), including through the use of end-to-end digital technologies. It has been proved that in various phases of the economic cycle, effective resource provision of solvation processes in the system of industrial innovations is of decisive importance, which means not only the rational distribution of limited resources between the participants of innovative solvations but also their lean and waste-free use in the production process.

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Usacheva, Tatiana R., Kseniya I. Kuz'mina, Mikhail A. Cheshinskiy, Irina A. Kuz'mina e Valentin A. Sharnin. "DATABASE ON THERMODYNAMIC PARAMETERS OF REACTIONS OF COMPLEXATION AND SOLVATION IN MIXED SOLVENTS". IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 59, n.º 3 (12 de julho de 2018): 86. http://dx.doi.org/10.6060/tcct.20165903.5295.

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Study of the effect of solvation on the thermodynamics and kinetics of complexation reactions in mixed solvents are performed in ISUCT and they are one of the main scientific directions of the university. For systematization of thermodynamic parameters of complexation and solvations in the mixed solvents which were obtained by researchers of ISUCT the database «Thermodynamics of a complex formation and solvation in binary solvents» was developed using a MS Access Database Management System which provides fast search of necessary thermodynamic characteristics and also information on the used methods of researches.

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Ma, Mengying, Renzhi Huang, Min Ling, Yong‐Sheng Hu e Huilin Pan. "Towards stable electrode–electrolyte interphases: Regulating solvation structures in electrolytes for rechargeable batteries". Interdisciplinary Materials 2, n.º 6 (novembro de 2023): 833–54. http://dx.doi.org/10.1002/idm2.12131.

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AbstractRechargeable batteries are highly in demand to power various electronic devices and future smart electric grid energy storage. The electrode–electrolyte interphases play a crucial role in influencing the electrochemical performance of batteries, with the solvation chemistries of the electrolyte being particularly significant in regulating these interfacial reactions. However, the reaction mechanisms of electrolyte solvation and their specific functions in batteries are not yet fully understood. In this review, we embark on an exploration of the fundamental principles governing solvation and present a comprehensive overview of how solvation structures impact interfacial reactions at the electrode–electrolyte interface. We underscore the significance of interactions among cations, anions, and solvents in shaping electrolyte solvation structures. The primary strategies for controlling solvation structures are also discussed, including the optimization of salt concentrations, solvent interactions, and the introduction of functional cosolvents. Furthermore, we elucidate the oxidation/reduction reaction mechanisms of electrolyte components in different solvation structures and the new understanding of electrolyte additives in modulating interfacial chemistries in batteries. Additionally, we emphasize the importance of incorporating new characterization techniques and theoretical simulations to attain a deeper understanding of the intricate processes taking place within batteries. This review provides an in‐depth understanding in solvations and interphasial properties and new ideas for designing advanced functional electrolytes for rechargeable batteries.

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Anema, Skelte G., e Lawrence K. Creamer. "Effect of the A and B variants of both αs1- and κ-casein on bovine casein micelle solvation and κ-casein content". Journal of Dairy Research 60, n.º 4 (novembro de 1993): 505–16. http://dx.doi.org/10.1017/s0022029900027862.

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SummaryCasein micelle solvation, a micelle characteristic that is sensitive to many factors, has been measured by a centrifugation technique at 30 °C for a series of uncooled fresh skim milks at pH 6·3, 6·6, 6·9 and 7·1. The relative αs-(αs1- plus αs2-), β– and κ-casein contents of all centrifuge pellets and supernatants were determined by a standardized electrophoretic method. The calcium and phosphate contents of a number of the pellets and milk samples were also determined. Solvation of micelles from milks with various genetic variants of β-lactoglobulin (A and B), αs1-casein (A and B) and κ-casein (A and B) was often found to be lower for milks containing either the B variant of αs1-casein or the A variant of κ-casein. It was also found that these two variant caseins were associated with a lower κ-casein content of the milks and the micelles, which is consistent with the lower solvation as κ-casein is associated with smaller micelle size and greater solvation. The solvations also seemed to increase during the lactation period. It is possible that some of the other features of milk and its products that have been ascribed to the differences in functional character between the A and B variants of αs1-casein may be partly caused by the increased level of κ-casein. The reason for the association of the A variant of αs1-casein with higher concentrations of κ-casein (and micelle solvation) is not obvious but possibly the haplotype αs1-casein A, β-casein A1, κ-casein A contains a controlling sequence in the chromosomal DNA that enhances expression of the κ-casein gene.

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Schreiber, Henry D., e M. Todd Coolbaugh. "Solvations of redox ions in glass-forming silicate melts". Journal of Non-Crystalline Solids 181, n.º 3 (fevereiro de 1995): 225–30. http://dx.doi.org/10.1016/s0022-3093(94)00516-8.

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IZUTSU, Kosuke. "Electrochemical approach to ion solvations. Applications of ion-selective electrodes as sensors for ion solvations and the problem of the liquid junction potential between different solvents. A review." Analytical Sciences 7, n.º 1 (1991): 1–8. http://dx.doi.org/10.2116/analsci.7.1.

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Okuno, Yoshishige. "Microscopic description of nonadiabatic, nonequilibrium, and equilibrium solvations for solvated cluster reactions: (H2O)nCl−+CH3Cl→ClCH3+Cl−(H2O)n". Journal of Chemical Physics 105, n.º 14 (8 de outubro de 1996): 5817–29. http://dx.doi.org/10.1063/1.472424.

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Liu, Shiyuan, Shijie Xu, Weiwei Tang, Bo Yu, Baohong Hou e Junbo Gong. "Revealing the roles of solvation in D-mannitol's polymorphic nucleation". CrystEngComm 20, n.º 46 (2018): 7435–45. http://dx.doi.org/10.1039/c8ce01222a.

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Faraji, Mohammad, e Ali Farajtabar. "Solvatochromism of naringenin in aqueous alcoholic mixtures". Journal of the Serbian Chemical Society 81, n.º 10 (2016): 1161–69. http://dx.doi.org/10.2298/jsc160327060f.

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The spectral change of naringenin was studied by Uv-vis spectrophotometric method in binary mixtures of water with methanol, ethanol and 1-propanol at 25?C. The effect of solvent was investigated by analysis of electron transition energy at the maximum absorption wavelength as a function of Kamlet and Taft parameters of mixtures by means of linear solvation energy relationships. The nonlinear response of solvatochromism was explained based on solute-solvent and solvent-solvent interactions. The possible preferential solvation of naringenin by each of solvents was studied through a modified preferential solvation model which considers the hydrogen bonding interactions between the prior solvents due to solvent-solvent interactions. The preferential solvation parameters and local mole fraction distribution around the solute were calculated. Results indicate that naringenin prefers to be more solvated by the complex solvating species and organic solvents than water.

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Cao, Xia, Peiyuan Gao, Xiaodi Ren, Lianfeng Zou, Mark H. Engelhard, Bethany E. Matthews, Jiangtao Hu et al. "Effects of fluorinated solvents on electrolyte solvation structures and electrode/electrolyte interphases for lithium metal batteries". Proceedings of the National Academy of Sciences 118, n.º 9 (25 de fevereiro de 2021): e2020357118. http://dx.doi.org/10.1073/pnas.2020357118.

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Electrolyte is very critical to the performance of the high-voltage lithium (Li) metal battery (LMB), which is one of the most attractive candidates for the next-generation high-density energy-storage systems. Electrolyte formulation and structure determine the physical properties of the electrolytes and their interfacial chemistries on the electrode surfaces. Localized high-concentration electrolytes (LHCEs) outperform state-of-the-art carbonate electrolytes in many aspects in LMBs due to their unique solvation structures. Types of fluorinated cosolvents used in LHCEs are investigated here in searching for the most suitable diluent for high-concentration electrolytes (HCEs). Nonsolvating solvents (including fluorinated ethers, fluorinated borate, and fluorinated orthoformate) added in HCEs enable the formation of LHCEs with high-concentration solvation structures. However, low-solvating fluorinated carbonate will coordinate with Li+ ions and form a second solvation shell or a pseudo-LHCE which diminishes the benefits of LHCE. In addition, it is evident that the diluent has significant influence on the electrode/electrolyte interphases (EEIs) beyond retaining the high-concentration solvation structures. Diluent molecules surrounding the high-concentration clusters could accelerate or decelerate the anion decomposition through coparticipation of diluent decomposition in the EEI formation. The varied interphase features lead to significantly different battery performance. This study points out the importance of diluents and their synergetic effects with the conductive salt and the solvating solvent in designing LHCEs. These systematic comparisons and fundamental insights into LHCEs using different types of fluorinated solvents can guide further development of advanced electrolytes for high-voltage LMBs.

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El Kazzi, Mario. "Li-ion solvation in TFSI and FSI -based ionic liquid electrolytes probed by X-ray photoelectron spectroscopy". EPJ Web of Conferences 273 (2022): 01001. http://dx.doi.org/10.1051/epjconf/202227301001.

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For Li-ion batteries, the Li-ion solvation in liquid electrolytes is a crucial parameter affecting directly the electrochemical cycling performance. X-ray photoelectron spectroscopy (XPS) can play an essential role for investigating the cation and anion electronic structure and monitoring the Li-ion solvation into various solvent and salt environments. In this contribution, we demonstrate the capability of conventional laboratory XPS using Al Kα X-ray source to determine the anions solvation shell of Li+ cation within the low vapour pressure and vacuum compatible ionic liquid electrolytes. 1M of LiTFSI and 1M of LiFSI salts dissolved in (EMIM+-FSI-) and (EMIM+-TFSI-) ionic liquids respectively are investigated by acquiring the F1s, N1s, C1s, S2p and Li1s core levels. The binding energy difference between the N1s component originating from the EMIM+ cation and the N1s component originating from TFSI- or FSIanions solvating the Li+ confirms that both TFSI- and FSIcontribute simultaneously to the Li+ solvation. Additionally, the stability of the TFSI and FSI -based ionic liquid electrolytes is carefully discussed for long X-ray exposure times.

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Palmer, Bentley J., e Ross H. Hill. "The energetics of the oxidative addition of trisubstituted silanes to photochemically generated (η5-C5R5)Mn(CO)2". Canadian Journal of Chemistry 74, n.º 11 (1 de novembro de 1996): 1959–67. http://dx.doi.org/10.1139/v96-223.

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The rates for the oxidative addition reaction of trisubstituted silanes (Et3SiH, Et2MeSiH, EtMe2SiH, Et2SiH2) to photochemically generated (η5-C5R5)Mn(CO)2 (R5 = H5, Me5, H4Me) species have been measured for the temperature range 70–125 K. The reactions were carried out in either neat silane or a 50/50, by volume, mixture of methylcyclohexane and silane. The activation energies, determined using Arrhenius law, varied from 2 to 35 kj/mol. The kinetic data fit an isokinetic relationship with an isokinetic temperature of 102 ± 6 K. The results are interpreted in terms of a variation in the loss of solvation prior to the oxidative addition. When the solvating molecule is methylcyclohexane, then loss of the solvent molecule precedes oxidative addition. In cases where solvation is by the silane, the incomplete loss of this silane precedes the oxidative addition. Key words: mechanism, oxidative addition, solvation.

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Pola, Martina, Michal A. Kochman, Alessandra Picchiotti, Valentyn I. Prokhorenko, R. J. Dwayne Miller e Michael Thorwart. "Linear photoabsorption spectra and vertical excitation energies of microsolvated DNA nucleobases in aqueous solution". Journal of Theoretical and Computational Chemistry 16, n.º 04 (4 de abril de 2017): 1750028. http://dx.doi.org/10.1142/s0219633617500286.

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Employing density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations in combination with the semiclassical nuclear ensemble method, we have simulated the photoabsorption spectra of the four canonical DNA nucleobases in aqueous solution. In order to model the effects of solvation, for each nucleobase, a number of solvating water molecules were explicitly included in the simulations, and additionally, the bulk solvent was represented by a continuous polarizable medium. We find that the effect of the solvation shell in general is significant, and its inclusion improves the realism of the spectral simulations. The involvement of lone electron pairs in the hydrogen bonding with the solvating water molecules has the effect of systematically increasing the energies of vertical excitation into the [Formula: see text]-type states. Apart from a systematic blue shift of around [Formula: see text][Formula: see text]eV observed in the absorption peaks, the calculated photoabsorption spectra reproduce the measured ones with good accuracy. The photoabsorption spectra are dominated by excited states with [Formula: see text] and partial [Formula: see text] character. No low-energy charge transfer states are observed with the use of the CAM-B3LYP and M06-2X functionals.

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Deng, Zhongyi, e Donald E. Irish. "A Raman spectral study of solvation and ion association in the systems LiAsF6/CH3CO2CH3 and LiAsF6/HCO2CH3". Canadian Journal of Chemistry 69, n.º 11 (1 de novembro de 1991): 1766–73. http://dx.doi.org/10.1139/v91-259.

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The structure of the solvated lithium cation in methyl acetate (MA) solutions has been investigated using Raman spectroscopy. Two bands at 844 and 864 cm−1 have been assigned to two different types of MA: the former is from the bulk solvent and the latter arises from MA molecules solvating the lithium cation. From measurement of changes in intensity of these bands with increasing salt concentration a solvation number of four for Li+ in MA has been inferred. Changes in the Raman bands at ca. 1740 cm−1 suggest that solvation occurs through the carbonyl group. Evidence for contact ion pairing between Li+ and AsF6− is also presented. An equilibrium between solvent-shared ion pairs and contact ion pairs is proposed for which an equilibrium constant is estimated. The system LiAsF6/methyl formate (MF) is similar in structure. Key words: Raman, ion pair formation, lithium and hexafluoroarsenate ions, methyl acetate and formate, lithium ion solvation.

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Persson, I. "Solvation and complex formation in strongly solvating solvents". Pure and Applied Chemistry 58, n.º 8 (1 de janeiro de 1986): 1153–61. http://dx.doi.org/10.1351/pac198658081153.

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Chialvo, Ariel A., e Oscar D. Crisalle. "Solvent and H/D Isotopic Substitution Effects on the Krichevskii Parameter of Solutes: A Novel Approach to Their Accurate Determination". Liquids 2, n.º 4 (15 de dezembro de 2022): 474–503. http://dx.doi.org/10.3390/liquids2040028.

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We establish a direct route for the accurate determination of the solvent effect on the Krichevskii parameter of a solute, based solely on the contrasting solvation behavior of the solute in the desired solvent relative to that of the reference solvent, i.e., in terms of the distinct solvation Gibbs free energies of the solute and the corresponding Krichevskii parameters of an ideal gas solute in the pair of solvents. First, we illustrate the proposed approach in the determination of the H/D−solvent effect on the Krichevskii parameter of gaseous solutes in aqueous solutions, when the solvents are different isotopic forms (isotopomers) of water, and then, by generalizing the approach to any pair of solvents. For that purpose, we (a) identify the links between the standard solvation Gibbs free energy of the i−solute in the two involved solvent environments and the resulting Krichevskii parameters, (b) discuss the fundamentally based linear behavior between the Krichevskii parameter and the standard solvation Gibbs free energy of the i−solute in an α−solvent, and interpret two emblematic cases of solutions involving either an ideal gas solute or an i−solute behaving identically as the solvating species, as well as (c) provide a novel microstructural interpretation of the solvent effect on the Krichevskii parameter according to a rigorous characterization of the critical solvation as described by a finite unambiguous structure making/breaking parameter Siα∞(SR) of the i−solute in the pair of α−solvents.

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Acree, William E., Denise C. Wilkins e Sheryl A. Tucker. "Spectrofluorometric Probe Method for Examining Preferential Solvation in Binary Solvent Mixtures". Applied Spectroscopy 47, n.º 8 (agosto de 1993): 1171–74. http://dx.doi.org/10.1366/0003702934067900.

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A spectrofluorometric method is developed to examine preferential solvation of a probe molecule dissolved in binary solvent mixtures. The method assumes that the solvational sphere around every fluorophore is solvated by only one type of solvent component and that each solvated fluorophore contributes to the measured emission intensity. Expressions derived from the model are illustrated with the use of observed fluorescence emission behavior of 3,4-dihydrobenzo[ghilperylene dissolved in binary n-heptane + 1,4-dioxane and dibutyl ether + acetonitrile solvent mixtures, which were measured as part of the present study.

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Hemdan, Sokaina, e Radwan Alnajjar. "The non-ideality in binary aqueous systems contributed to the different abilities of solvent entities incorporated in the solvation shell of methylene blue". Journal of the Serbian Chemical Society, n.º 00 (2023): 87. http://dx.doi.org/10.2298/jsc230512087h.

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The solvatochromic properties of methylene blue (MB) were investigated in neat water, methanol, ethanol, propanol, dioxane, and their corresponding aqueous mixtures. The correlation of the empirical solvent polarity scale (ET) values of MB with solvent composition was analyzed using the solvent exchange model of Bosch and Roses to explain the preferential solvation of the probe thiazine dye in the binary mixed solvents. Non-linear solvatochromism of MB was observed in aqueous mixtures of methanol, ethanol, propanol, and dioxane. The influence of the composition of the solvating shell in preferential solvation of the solute dye was investigated in terms of both solvent-solvent and solute-solvent interactions, and the local mole fraction of each solvent composition in the cybotactic region of the probe was also calculated. Effective mole fraction variation can provide important physicochemical insights into the microscopic and molecular interactions between MB species and solvent components. The results showed that the MB solvation shell was thoroughly saturated with the solvent complex S12 for dioxane more than ethanol and propanol mixtures, and opposite trends for methanol mixtures, whereas the solvent complex S12 could not incorporate into the MB solvation shell. Data from the binary systems were analyzed with KAT parameters using a dual model of basicity and polarity. The results showed that the polarity was better suited for spectral shift in aqueous methanol and ethanol solutions, while the basicity was better for aqueous propanol and dioxane solutions.

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Serhieieva, Yevheniia, Anton Zakharov e Sergey Kiyko. "Peculiarities of solvatochromism of 4-[[(2,4-dinitrophenyl)methylene]imino-2,6-diphenyl]phenol and Reichardt’s dye. DFT calculations". Kharkov University Bulletin Chemical Series, n.º 38 (14 de junho de 2022): 23–30. http://dx.doi.org/10.26565/2220-637x-2022-38-03.

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One of the current directions of development of modern physical chemistry is the working out of sensor devices and molecular probes for the study of various properties of solutions, colloidal systems and biological objects. The latter include solvatochromic dyes, which, thanks to Reichardt's classic works, have found wide application for quantitative assessment of the solvating ability of individual and, to a lesser extent, mixed solvents of various nature. The different behavior of Reichardt and 4-[[(2,4-dinitrophenyl)methylene]imino-2,6-diphenyl]phenol dyes in pure water and mixed water-organic solvents, when their composition is changed, indicates that their electronic structure undergoes a fundamental change during the transition from the ground state to the first excited state. The aim of the work was to study and compare the HOMO and LUMO structure of the standard Reichardt betaine dye and the 4-[[(2,4-dinitrophenyl)methylene]imino-2,6-diphenyl]phenol dye using the stationary and time-dependent density functional theory (DFT). It is proved that the 4-[[(2,4-dinitrophenyl)methylene]imino-2,6-diphenyl]phenol dye has two active exchangeable solvation centers and therefore has an excellent solvation mechanism, at least in aqueous solution, compared to Reichardt dye, which should appear upon its solvation also in mixed water-organic solvents with a high water content in them.

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Louis, C., A. Bebba e J. Bessière. "Solvation properties in iso-acidic media involving phosphoric acid". Canadian Journal of Chemistry 66, n.º 9 (1 de setembro de 1988): 2422–27. http://dx.doi.org/10.1139/v88-381.

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Concentrated solutions of mineral acids (phosphoric, hydrochloric, perchloric, sulfuric) are characterized, for an equal value of their water activity, by an equal R0(H) acidity level (iso-acidic solutions). By mixing them, we prepare what we call iso-acidic mixtures which keep the same acidity level as the constitutive solutions whatever the proportions; their redox and solvating properties depend both on the nature and on the ratio of the constitutive solutions. Reactivity variations for ionic species: Cl−, Br−,I−, diethyldithiophosphate (LET−), Si(W3Ol0)44−, Si(W3O10)45−, Cu2+, Cu+, Pb2+, Sn2+, Cd2+, Zn2+, Ag+, Fe3+, Fe2+, UO22+, U4+ in the iso-acidic mixtures are characterized by their ƒ solvation-transfer activity coefficients. Relations between ƒ coefficient values and complexation properties are established and it is shown that phosphoric acid has comparatively weak solvating properties toward most species. The possibility for anticipating reaction changes with the iso-acidic mixture composition by using the ƒ coefficients is demonstrated in the case of cadmium ionic flotation with diethyldithiophosphate and silver extraction with dithizone in carbon tetrachloride.

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Lim, Minhong, Jiyeon Seo e Hongkyung Lee. "Modulating Ionic Transport and Interface Chemistry Via Surface-Modified Nanoparticle Carrier in Silica-Colloidal Electrolyte for Li-Metal Batteries". ECS Meeting Abstracts MA2023-01, n.º 55 (28 de agosto de 2023): 2669. http://dx.doi.org/10.1149/ma2023-01552669mtgabs.

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Tailoring the Li+ solvating environment and solid-electrolyte interface (SEI) chemistry is crucial for developing long-life lithium (Li) metal batteries. However, it is hard to reinforce at the same time, fully solvating Li+ for fast ionic transport and forming anion-derived SEI, due to both being strongly related. Here, we report a CA-modified SiO2 dispersed colloidal electrolyte (C-SCE) for modulating the Li+ solvation structure and interface chemistry, simultaneously. SiO2 nanoparticle migration can act as an additive and anion carrier toward the Li surface, tailoring the Li+ solvating environment and SEI chemistry. We further render more active sites for intermolecular hydrogen bonds between neighboring complex anions and solvent molecules, using CA-tethered SiO2 in colloidal electrolytes. Chemisorption of CA can further dissociate the Li+ from anions allowing selective Li+ transport, resulting in a high Li+ transference number (~0.78). Also, SiO2 nanoparticle migration can act as an additive and anion carrier toward the Li surface, SEI chemistry. More ingredients delivered by CA-tethered SiO2 carriers reinforce the SEI via co-implantation of SiO2 and fluorinated components. Furthermore, C-SCE demonstrates Li dendrite suppression and stable cycling stability (>100 cycles at 70% of initial capacity) of LMBs under stringent conditions (lean electrolyte (6 g Ah−1), high loading (4.8 mAh cm−2), thin Li metal (50 µm)). Figure 1

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Pandey, Dinesh, e Seema Kothari. "Kinetics and Mechanism of the Oxidation of Dl-Methionine by Benzimidazolium Dichromate". Progress in Reaction Kinetics and Mechanism 34, n.º 3 (agosto de 2009): 199–209. http://dx.doi.org/10.3184/146867809x466221.

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The oxidation of DL-methionine (MT) by benzimidazolium dichromate (BIDC), in dimethyl sulfoxide, leads to the formation of the corresponding sulfoxide. The reaction is first order with respect to BIDC. Michaelis - Menten type kinetics were observed with respect to MT. The reaction is catalysed by hydrogen ions and the dependence is of the form kobs = k‘[H+]. The rate of oxidation of MT was determined in 19 organic solvents. An analysis of the solvent effect by solvatochromic equations indicated that though both the anion- and cation-solvating powers of the solvent contribute to the observed solvent effect, the role of cation-solvation is much the major. A suitable mechanism has been proposed.

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Moon, Junyeob, Dongok Kim, Lieven Bekaert, Munsoo Song, Jinkyu Chung, Danwon Lee, Annick Hubin e Jongwoo Lim. "Non-Fluorinated Diluent in Localized High Concentration Electrolytes Enabling Superior Performance of Lithium Metal Negative Electrode Battery". ECS Meeting Abstracts MA2023-01, n.º 2 (28 de agosto de 2023): 546. http://dx.doi.org/10.1149/ma2023-012546mtgabs.

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Localized high-concentration electrolytes (LHCEs) are very promising strategies for the high-energy-density lithium (Li) metal batteries (LMBs). Nonsolvating diluents introduced in the LHCEs plays a critical role in physicochemical properties of LHCE and the overall LMB performance. However, there is a lack of design strategies for ideal nonsolvating diluents, and the reported cases are limited to fluorinated nonsolvating diluents (FNDs). FNDs suffer from accelerated decomposition at lithium metal, leading to electrolyte dry-up and ultimately battery failure. Furthermore, the high cost and potential environmental hazards of FNDs necessitate the development of non-fluorinated nonsolvating diluents (NFNDs). Here, we present a design rule for the ideal NFNDs by spectroscopically characterizing the Li+ solvation ability and miscibility. Our design rule identifies the ideal NFNDs, based on the superior cycling performane of candidate diluents over 350 cycles (99.0% ethoxybezene), 500 cycles (98.5% anisole), and 1400 cycles (99.0%, furan). NMR spectra revealed that the designed NFNDs were highly stable in electrolytes during extended cycles. Raman spectroscopy and theoretical calculation reveal that resonance of an electron pair on the oxygen atom of NFND molecules decreases the lithium-ion solvation ability, thereby achieving desirable non-solvating characteristics while maintaining good miscibility, superior cathodic stability, and low prices. Figure 1

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Mandal, Urmila, Sumita Sen, Kaushik Das e Kiron Kumar Kundu. "Kinetic solvent effects on alkaline decolorization of crystal violet in some aquo-organic solvents". Canadian Journal of Chemistry 64, n.º 2 (1 de fevereiro de 1986): 300–307. http://dx.doi.org/10.1139/v86-050.

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Rate constants (ks) of alkaline fading of crystal violet (CV+) have been determined at 25 °C by spectrophotometric measurements in aqueous mixtures of some protic, aprotic, and dipolar aprotic cosolvents. Transfer free energies of the substrate (CV+), [Formula: see text], were also determined in some of the solvent systems from solubility measurements of the chloride salt, and by subtracting [Formula: see text] obtained earlier by use of the tetraphenylarsonium tetraphenylboron (TATB) extrathermodynamic assumption. This helped determine transfer free energies of the transition state (X≠), [Formula: see text] values of lyate ion (S−) based on the TATB assumption are already known for all of these solvent systems. The observed log (ks/kw) – composition profiles reveal that the relative solvation of the reacting species rather than the dielectric constant of the solvents dictates the complex variation of the rates of the reaction in these solvent systems. Correlation of [Formula: see text] with [Formula: see text] indicates that the reaction is largely controlled by the relative solvation of S− in most of the cases. But analysis of [Formula: see text] – composition profiles for some of the solvent systems reveals that the non-compensation of the [Formula: see text] contributions of initial-state substrate and of the transition-state complex, which may be considered to be an outer-sphere complex [CV+](S−), is also in accord with what is expected from the relative solvating characteristics of the cosolvents as guided by their respective physico-chemical properties.

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Biddinger, Elizabeth J., Michael Keating, Elijah Bernard, Sharon Lall-Ramnarine e Robert J. Messinger. "Ionic Liquid - Glyme Mixtures to Modify Solvation Chemistry, Electrochemical and Physiochemical Properties in Lithium Containing Electrolytes". ECS Meeting Abstracts MA2023-02, n.º 56 (22 de dezembro de 2023): 2728. http://dx.doi.org/10.1149/ma2023-02562728mtgabs.

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Pyrrolidinium-based ionic liquids are an intriguing material for lithium-based battery electrolytes due to their inherit non-flammability and large electrochemical windows. Poor lithium-ion transport in ionic liquid-based electrolytes hinder the effectiveness of these electrolytes. Solvate ionic liquids were introduced as a subclass of ionic liquids consisting of high concentrations of lithium salts and glymes. For example, the solvate ionic liquid Li(G4)TFSI is an equimolar ratio of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and tetraethylene glycol dimethyl ether (G4). In this work, pyrrolidinium-based ionic liquids containing short polyether side chains, structurally analogous to glymes, are mixed with equimolar amounts of LiTFSI and varying portions of G4. These tertiary mixtures were evaluated based on the ratio of solvating oxygen to lithium ion ([O]/[Li+]) present in the mixture. Trends in the oxidative stability, conductivity and lithium transference number were evaluated from mixtures of [O]/[Li+] between 5 to 8. Oxidative stability of tertiary mixtures with [O]/[Li+] = 5 showed improved oxidative stability compared to the binary Li(G4)TFSI, while [O]/[Li+] > 5 had diminished oxidative stability. DSC thermal analysis between -85°C to +120°C showed the tertiary mixtures helped suppress the glass transition temperature of Li(G4)TFSI to lower temperatures. Changes in the solvation structures were evaluate using spectroscopic analysis, including Raman spectroscopy. The changes in the solvation chemistry were correlated to the physiochemical and electrochemical properties.

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Bünnemann, Karoline, e Christian Merten. "Solvation of N,C-Protected Valine: Interactions with DMSO and a Chiral Solvating Agent". Journal of Physical Chemistry B 120, n.º 35 (25 de agosto de 2016): 9434–42. http://dx.doi.org/10.1021/acs.jpcb.6b05897.

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27

Jia, Hao, Ju-Myung Kim, Peiyuan Gao e Wu Xu. "(Digital Presentation) Effects of Solvents and Additives in Non-Conventional Liquid Electrolytes for Lithium-Ion Batteries". ECS Meeting Abstracts MA2022-01, n.º 2 (7 de julho de 2022): 193. http://dx.doi.org/10.1149/ma2022-012193mtgabs.

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Lithium (Li)-ion batteries (LIBs) have now been the major power sources in consumer electronic devices and electric vehicles. To further enhance the battery performances, more efforts are required to address significant challenges in improving cycle life, rate capability, energy density, working temperature range and safety of state-of-the-art LIBs. The conventional LiPF6/carbonate electrolytes have been found unable to meet all the requirements for advanced LIBs with high-capacity cathodes and anodes although proper additives can improve the battery performances in certain aspects. For instance, the presence of acidic species like HF in LiPF6 electrolytes and specifically at elevated temperatures is still detrimental to the layered oxide cathodes and the electrode/electrolyte interphases, and the issue of electrochemical oxidation stability of conventional electrolytes at voltages over 4.3 V needs to be addressed for the high-voltage cathodes and batteries. In response to the challenges facing to the conventional LiPF6/carbonate electrolytes in LIBs, especially the long-term cycling stability, non-conventional electrolytes based on functional localized high-concentration electrolytes (LHCEs) have been developed for LIBs in recent years. Due to the unique solvation structures of LHCEs, LHCEs lead to formation of thin, compact and uniform electrode/electrolyte interphases, thus greatly improve LIB performances. In this work, we comparatively studied the effects of solvating solvents and additives in LHCEs on the solvation structures and properties of LHCEs as well as the battery performance of LIBs with nickel-rich cathode and graphite anode. More details will be reported during the presentation.

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Hossain, Md Jamil, Qisheng Wu, David C. Bock, Amy C. Marschilok, Kenneth J. Takeuchi, Esther S. Takeuchi e Yue Qi. "Designing Localized High Concentration Electrolytes Based on Fluorinated Solvents for Lithium-Ion Batteries". ECS Meeting Abstracts MA2023-01, n.º 2 (28 de agosto de 2023): 650. http://dx.doi.org/10.1149/ma2023-012650mtgabs.

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Reduction at the anode can affect electrolyte decomposition, solid electrolyte interphase (SEI) formation and growth, and thus the lithium solvation/de-solvation near the SEI, and ultimately lead to various perilous side reactions such as inactive lithium formation. Lithium ions solvated in the electrolyte solution along with salt anions diffuse towards the surface of the electrode. At the charged surface, these solvated ions can undertake different pathways leading to various reductive decomposition products to subsequently form the SEI. The transfer of electrons from the electrode to the salt anions form inorganic SEI products. The SEI layer gradually thickens during repeated charge/discharge cycles due to electron exposure to electrolyte or electrolyte diffusion to the anode surface. This gradual thickening of SEI layer decreases active lithium ions, solvents, and salts and increases cell resistance and lowers the cell capacity and Coulombic efficiency. Essentially, the choice of electrolytes has a significant influence on the formation of an SEI and its underlying chemical and mechanical properties. Optimizing the electrolytes is crucial for an SEI formation since the properties of the SEI significantly affect the lithium-ion batteries’ cyclability, life time, capacity retention, high power density, rate capability, and safety. One approach of stabilizing the SEI is to utilize an electrolyte with high concentration of salt, also known as High-Concentration Electrolytes (HCEs). This approach modifies the Li+ solvation structure to form contact ion pairs (CIP) and aggregates (AGG) while decreasing solvent-separated ion pairs (SSIPs) so that the salt anion, such as FSI-, is preferentially decomposed to form a robust LiF-rich SEI. LiF is considered a beneficial SEI component to block electron transport. By introducing a diluent (a non-solvating solvent) in the HCE to form Localized High Concentration Electrolyte (LHCE), the disadvantages of the HCE, such as low ionic conductivity, high viscosity and high cost, can be minimized while retaining the highly concentrated salt-solvent clusters as they are in the HCE. LHCEs based on fluorinated solvents and diluents can further stabilize the electrode-electrolyte interface. Recent studies showed that the presence of fluorine in the SEI, either in the form of simple inorganic fluorides (LiF) or organofluoro-moieties, brought positive impacts such as expanded electrochemical stability window and high ionic transport. Fluorinated solvents can shift the oxidation stability to a higher voltage compared to their nonfluorinated counterparts. Fluorinated electrolytes enable a high lithium plating Coulombic efficiency and suppresses lithium dendrite formation to a greater extent. In this work we focused on identifying the selection rules for the diluent for designing LHCEs to preserve or improve the local high salt concentration clusters to facilitate the formation of an inorganic rich anion derivative film on the anode as well as to enhance ionic conductivity to enable fast charging. Some of the important properties to consider while selecting a diluent are: - diluent molecules must offer little or no solubility to the salt so that they have minimal participation in the solvation clusters, they must be readily miscible with the solvating solvent so that they dissolve and remove some solvent molecules from the clusters; effectively increasing the salt concentration in the solvation clusters, diluents should be distributed on the periphery of salt-solvent clusters, diluents should have low viscosity, to reduce the overall viscosity of the formulated electrolyte, which in turn improves the ionic conductivity since the low viscosity of diluents allow for higher mobility of the ionic clusters. We analyzed LHCEs consisting of different diluents and diluent molar ratios in a comparative fashion to understand their properties in retaining or improving the structures of the high concentration salt-solvent clusters and improving ionic conductivity. We varied the diluent molar ratio to understand its relationship to increasing salt concentration gradients in the center of the solvent-salt clusters. We also analyzed the relationship between diluent molar ratio and ionic conductivity and found that an optimum diluent molar ratio exists for which the ionic conductivity can be maximized. Our findings serve as design guidelines for practical applications of LHCEs.

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Kalyagin, Alexander, Lubov Antina, Alexander Ksenofontov, Elena Antina e Mikhail Berezin. "Solvent-Dependent Fluorescence Properties of CH2-bis(BODIPY)s". International Journal of Molecular Sciences 23, n.º 22 (19 de novembro de 2022): 14402. http://dx.doi.org/10.3390/ijms232214402.

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Biocompatible luminophores based on organic dyes, which have fluorescence characteristics that are highly sensitive to the properties of the solvating medium, are of particular interest as highly sensitive, selective, and easy-to-use analytical agents. We found that BODIPY dimers (2,2′-, 2,3′-3,3′-CH2-bis(BODIPY) (1–3)) demonstrate fluorescence characteristics with a high sensitivity to the presence of polar solvents. The intense fluorescence of 1–3 in nonpolar/low-polarity solvents is dramatically quenched in polar media (acetone, DMF, and DMSO). It has been established that the main reason for CH2-bis(BODIPY) fluorescence quenching is the specific solvation of dyes by electron-donating molecules (Solv) with the formation of stable supramolecular CH2-bis(BODIPY)·2Solv structures. Using steady-state absorption and fluorescence spectroscopy, time-resolved fluorescence spectroscopy, and computational modeling, the formation mechanism, composition, and structure of CH2-bis(BODIPY)·2Solv supramolecular complexes have been substantiated, and their stability has been evaluated. The results show the promise of developing fluorescent probes based on CH2-bis(BODIPY)s for detecting toxic N/O-containing compounds in solutions.

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30

Jay-Gerin, Jean-Paul. "Correlation between the electron solvation time and the solvent dielectric relaxation times τ2 and τL1 in liquid alcohols and water: towards a universal concept of electron solvation?" Canadian Journal of Chemistry 75, n.º 10 (1 de outubro de 1997): 1310–14. http://dx.doi.org/10.1139/v97-156.

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A simple model of electron solvation in polar liquids is presented, in which we attempt to link the electron solvation time τs to τ2, the time for reorientation of monomeric molecules, and to τL1, the longitudinal dielectric relaxation time of the solvent. It is shown that this model, which is suggested by the so-called hybrid model of electron solvation previously described for methanol, can satisfactorily account for electron solvation in all polar liquids, including linear alcohols (methanol to decanol), 1,2-ethanediol, H2O, and D2O, for which data are available from the literature. A close similarity is indeed obtained between our calculated values of τs and those measured experimentally. The observation of such a correlation supports a universal concept of electron solvation. Keywords: polar liquids, electron solvation time, solvent dielectric relaxation times, universal concept of electron solvation.

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31

Louis, C., e J. Bessière. "Propriétés de solvation des solutions concentrées en acide phosphorique". Canadian Journal of Chemistry 64, n.º 3 (1 de março de 1986): 608–14. http://dx.doi.org/10.1139/v86-098.

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Solvation properties of ions inH2O–H3PO4 media (1–14 M) are characterized with their solvation transfer activity coefficients f. These are calculated from normal potential or solubility values, and indicate an increasing solvation for anions and decreasing solvation for cations in concentrated acid solutions. For each species, the range depends on its number of charges, on the existence of oxygen atoms in its structure, and on its basic properties. The consequences of variation of solvation on oxidation–reduction reactions and solubility properties are studied.

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32

Pham, Thuy Duong, Abdullah Bin Faheem, Junam Kim, Hye Min Oh e Kyung‐Koo Lee. "Practical High‐Voltage Lithium Metal Batteries Enabled by Tuning the Solvation Structure in Weakly Solvating Electrolyte". Small 18, n.º 14 (25 de fevereiro de 2022): 2107492. http://dx.doi.org/10.1002/smll.202107492.

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33

Liu, Ping. "(Invited) Pushing Lithium-Metal Batteries to the Limit: Fast Charging, Low Temperature, and Safety". ECS Meeting Abstracts MA2022-02, n.º 5 (9 de outubro de 2022): 561. http://dx.doi.org/10.1149/ma2022-025561mtgabs.

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The performance of lithium metal batteries has advanced significantly, thanks to continuous improvement in the lithium metal anode. Many chemical and mechanical control strategies have been employed to combat its degradation mechanisms such as parasitic reactions, dendritic growth, and formation of isolated lithium. Electrolytes with high salt concentrations, including those with non-solvating diluents (known as localized high concentration electrolytes, or LHCE), electrolyte additives, artificial coatings, 3D plating hosts Li, and applying pressures in the 100s-1000s of kPa range have all been found to be effect in yielding dense, high efficiency Li metal deposits. Despite these advancements, reported lithium metal batteries tend to be charged at low rates, operated under ambient conditions, and lacking sufficient information on their safety characteristics. In this talk, we will review our recent progress in pushing the lithium metal batteries to extreme operating conditions in term of temperature, charging rates, and shorting behavior. To enable fast charging, we have focused on developing a nucleation agent on the surface of current collector that can induce the formation of large, uniform nucleation sites. These nanoscopic sites enable dense lithium plating at 5 mA c-2 of current density, when a planar Cu electrode will fail catastrophically. This uniform nucleation method leads to a 45 um thick Li deposit that is nearly porosity free. A lithium metal cell with a metal oxide cathode is capable of 1C charging for extended cycles. To enable low temperature operation, we have focused on the development of new electrolyte compositions that uses weakly solvating solvents. These electrolytes, represented by monodentate ethers and LHCEs made of ethers, promote the formation of contact ion pairs after solvation over solvent separated ion pairs. These electrolytes have enabled the formation of dense lithium metal deposits at as low as -60oC, while strongly solvating electrolytes will promote the formation of dendrites and cell shorting. Finally, any practical implementation of lithium metal batteries operating under these extreme conditions have to feature safety designs that mitigate the impact of internal shorting. In this regard, we have focused on separator designs that can detect and intercept lithium dendrites.

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CHIKASAKO, Yuzuru, Kentaro DOI e Satoyuki KAWANO. "F1-2 Molecular fluid dynamics of Li^+ ions forming solvation structures". Proceedings of The Computational Mechanics Conference 2010.23 (2010): _F—3_—_F—4_. http://dx.doi.org/10.1299/jsmecmd.2010.23._f-3_.

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SATO, H., A. MATSUZAKI, S. NISHIO, Y. HORIKI e O. ITO. "REACTIONS OF MONOVALENT METAL IONS (M+) WITH MIXED MOLECULAR CLUSTERS (NH3)m(H2O)n AS STUDIED BY LASER-ABLATION MOLECULAR BEAM (LAMB) METHOD: PREFERRED OR NONSPECIFIC COORDINATION". Surface Review and Letters 03, n.º 01 (fevereiro de 1996): 671–74. http://dx.doi.org/10.1142/s0218625x96001200.

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Three distinct types of competitive solvation around monopositive metal ions in the gas phase have been revealed by the laser-ablation molecular beam method using binary clusters in the molecular beam: (i) preferred solvation of one of the two components, (ii) essentially nonselective solvation, and (iii) magic-number-like behavior of one component in the presence of the other component in the outer solvation sphere.

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Ben-Naim, Arieh. "Solvation Thermodynamics and Its Applications". Entropy 26, n.º 2 (18 de fevereiro de 2024): 174. http://dx.doi.org/10.3390/e26020174.

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In this article, we start by describing a few “definitions” of the solvation processes, which were used in the literature until about 1980. Then, we choose one of these definitions and show that it has a simple molecular interpretation. This fact led to a new definition of the solvation process and the corresponding thermodynamic quantities. The new measure of the solvation Gibbs energy has a simple interpretation. In addition, the thermodynamic quantities associated with the new solvation process have several other advantages over the older measures. These will be discussed briefly in the third section. In the fourth section, we discuss a few applications of the new solvation process.

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Kim, Sang Cheol, e Yi Cui. "Probing Solvation Thermodynamics of Lithium Battery Electrolytes through Potentiometric Methods". ECS Meeting Abstracts MA2022-02, n.º 2 (9 de outubro de 2022): 164. http://dx.doi.org/10.1149/ma2022-022164mtgabs.

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The electrolyte is a principal component of a lithium battery that impacts almost every facet of the battery’s performance. Solvation of lithium ions in electrolyte solution is key to understanding the electrolyte, but our understanding of solvation lags behind its significance. Particularly, estimating solvation free energy has been largely limited to computational simulations. Despite their versatility, simulations can be computationally expensive, and experimental methods to complement simulations are desired. We have recently introduced a potentiometric technique to probe the relative solvation free energy of lithium ions in battery electrolytes. We devised an electrochemical cell composed of two half-cells, with symmetric electrodes but asymmetric electrolytes. Whereas the open circuit potential of a conventional lithium-ion battery measures the free energy differences of lithium ions in the two electrodes, our experimental setup measures the energy differences of the lithium ions in two different electrolytes. By measuring the cell potential with a reference electrolyte, we can quantitatively characterize lithium ion solvation energy of an electrolyte of interest. The effects of concentration, anion and solvent on solvation energy are explored and verified with simulations. Particularly, we establish a correlation between cell potential (Ecell) and cyclability of high-performance electrolytes for lithium metal anodes. We find that solvents with more negative cell potentials and positive solvation energies—those weakly binding to Li+—lead to improved cycling stability. Weaker solvents are conjectured to have more anion-rich solvation structures that lead to anion-derived solid-electrolyte interphases, a hypothesis supported by cryogenic electron microscopy. It reveals that weaker solvation is correlated to an inorganic anion-derived solid-electrolyte interphase that stabilizes cycling.

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Kimura, Yoshifumi. "Solvation heterogeneity in ionic liquids as demonstrated by photo-chemical reactions". Pure and Applied Chemistry 92, n.º 10 (25 de outubro de 2020): 1695–708. http://dx.doi.org/10.1515/pac-2019-1116.

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AbstractIt has been recognised that ionic liquids (ILs) with long alkyl-chains have a segregated structure due to the inhomogeneous distribution of polar parts and non-polar parts. This inhomogeneity of ILs brings about unique solvation phenomena of solute molecules dissolved in ILs. We have investigated various solvation-state selective phenomena by using laser spectroscopic techniques such as solvation state selective vibrational spectroscopy, translational and rotational dynamics of small molecules in ILs, and solvation state selective fundamental chemical reactions. In this paper, we have reviewed an intramolecular electron transfer (ET) reaction in the Marcus inverted region of N,N-dimethyl-p-nitroaniline and an intramolecular proton transfer (IPT) reaction in 4′-N,N-diethylamino-3-hydroxyflavone as examples of chemical reactions affected by unique solvation in ILs.

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Roy, Dipankar, e Andriy Kovalenko. "Multiscale Methods Framework with the 3D-RISM-KH Molecular Solvation Theory for Supramolecular Structures, Nanomaterials, and Biomolecules: Where Are We Going?" Thermo 3, n.º 3 (2 de julho de 2023): 375–95. http://dx.doi.org/10.3390/thermo3030023.

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3D-RISM-KH molecular solvation theory based on statistical mechanics has been an engine of the multiscale methods framework, which also includes molecular simulation techniques. Its applications range from the solvation energy of small molecules to the phase behavior of polymers and biomolecules. Molecular solvation theory predicts and explains the molecular mechanisms and functioning of a variety of chemical and biomolecular systems. This includes the self-assembly and conformational stability of synthetic organic rosette nanotubes (RNTs), the aggregation of peptides and proteins related to neurodegeneration, the binding of ligands to proteins, and the solvation properties of biomolecules related to their functions. The replica RISM-KH-VM molecular solvation theory predicts and explains the structure, thermodynamics, and electrochemistry of electrolyte solutions sorbed in nanoporous carbon supercapacitor electrodes, and is part of recent research and development efforts. A new quasidynamics protocol couples multiple time step molecular dynamics (MTS-MD) stabilized with an optimized isokinetic Nosé–Hoover (OIN) thermostat driven by 3D-RISM-KH mean solvation forces at gigantic outer time steps of picoseconds, which are extrapolated forward at short inner time steps of femtoseconds with generalized solvation force extrapolation (GSFE). The OIN/3D-RISM-KH/GSFE quasidynamics is implemented in the Amber Molecular Dynamics package. It is validated on miniprotein 1L2Y and protein G in ambient aqueous solution, and shows the rate of sampling 150 times faster than in standard MD simulations on these biomolecules in explicit water. The self-consistent field version of Kohn–Sham DFT in 3D-RISM-KH mean solvation forces is implemented in the Amsterdam Density Functional (ADF) package. Its applications range from solvation thermochemistry, conformational equilibria, and photochemistry to activation barriers of different nanosystems in solutions and ionic liquids.

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Faraji, Mohammad, e Ali Farajtabar. "Preferential solvation of quercetin in aqueous aprotic solvent mixtures". Journal of the Serbian Chemical Society 85, n.º 2 (2020): 227–36. http://dx.doi.org/10.2298/jsc190408037f.

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Solvatochromism of quercetin was studied in binary mixtures of water with dimethyl sulfoxide, N,N-dimethylformamide and N,N-dimethylacetamide at 25 ?C by UV?Vis measurements. For all mixtures, a non-linear trend was observed in spectral shifts plotted against the bulk mole fractions. Deviation from ideal behaviour indicates that the solvation shell of quercetin differs in composition from the bulk because of preferential solvation. The solvent exchange model was applied in the analysis of solvatochromic data in order to quantify the extent of preferential solvation in the case of solute?solvent and solvent?solvent intermolecular interactions. The results show that the solvation shell of quercetin is enriched in aprotic solvent and the complex that was formed by the interaction between water and an aprotic solvent, over the whole composition range. The distribution of the solvent species in the solvation cage was obtained from the calculation of the local mole fractions as a function the bulk composition. It shows that the solvent?solvent interactions have great influence on the solvation behaviour of quercetin in aqueous aprotic solvent mixtures.

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許澤天, 許澤天. "消極死亡協助與幫助自殺之刑法問題及對策". 月旦醫事法報告 57, n.º 57 (julho de 2021): 036–46. http://dx.doi.org/10.53106/241553062021070057003.

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Ramesh, B., D. Vijaya Bharathi, B. Kavitha e P. Manikyamba. "Linear Solvation Energy Relationship in the Reaction between Phenacyl Bromide and 2-Mercaptobenzothiazole". Progress in Reaction Kinetics and Mechanism 34, n.º 3 (agosto de 2009): 239–48. http://dx.doi.org/10.3184/146867809x466195.

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The reaction between phenacyl bromide and 2-mercaptobenzothiazole was studied conductometrically in 17 different protic and aprotic solvents. The second order rate constants determined are found to be highly susceptible to changes in the solvation abilities of the solvents. Correlation of the rate constants with different solvent parameters indicated that the solvation of the reactants and the transition state is due to the electrophilicity, hydrogen bond donor ability, specific polarisability and a non-specific polarity of the solvent. by statistical analysis, a linear solvation energy relationship is derived and the percentage contributions of each type of solvation are estimated.

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Inada, Y., Y. Tsutsui, H. Wasada e S. Funahashi. "Solvation Structure of Solvated Cu(I) Ions in Non-Aqueous Solvents as Studied by EXAFS and ab initio Molecular Orbital Methods". Zeitschrift für Naturforschung B 54, n.º 2 (1 de fevereiro de 1999): 193–99. http://dx.doi.org/10.1515/znb-1999-0207.

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The structure parameters around the Cu(I) ion in pyridine (PY), 4-methylpyridine (4MPY), 2-methylpyridine (2MPY), 2,6-dimethylpyridine (26DMPY), and acetonitrile (AN) were determined by the extended X-ray absorption fine structure (EXAFS) method. The solvation structures of the Cu(I) ion in PY, 4MPY, and AN are 4-coordinate tetrahedral with Cu-N bond lengths of 205, 205, and 200 pm, respectively. In the case of 2MPY and 26DMPY, the Cu(I) ion has a 3-coordinate triangular structure with a Cu-N bond length of 201 pm. Such a decrease in the coordination number was interpreted in terms of the bulkiness of the solvent molecules. In order to clarify the most stable solvation structure of the Cu(I) ion, we carried out ab initio molecular orbital calculations for the solvation system of [Cu(NCH)n]+ (n = 1 - 6 ) where the steric effect is negligible. The Gibbs free energy of solvation was the smallest in the case of n = 4 and the 4-coordinate tetrahedral solvation of the Cu(I) ion was theoretically evaluated as most stable. The enthalpy of solvation monotonously decreases with increasing n, while the entropy of solvation proportionally increases. Although a larger gain of enthalpy is observed for the octahedral structure rather than the tetrahedral one, the entropic loss for the former overcomes the enthalpic gain.

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Liu, Dongdong, Xunhui Xiong, Qianwen Liang, Xianwen Wu e Haikuo Fu. "An inorganic-rich SEI induced by LiNO3 additive for a stable lithium metal anode in carbonate electrolyte". Chemical Communications 57, n.º 73 (2021): 9232–35. http://dx.doi.org/10.1039/d1cc03676a.

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Bock, Hans, Andreas John, Christian Näther e Zdenek Havlas. "Elektronentransfer und Ionenpaar-Bildung, 34 [1 - 3] Einkristallstruktur des Solvens-separierten Radikalionenpaares [9,9′-Bianthryle·⊖][Na⊕(DME)3] / Electron Transfer and Ion Pair Formation, 34 [1-3] Single Crystal Structure of the Solvent-Separated Ion Pair [9,9′-Bianthryle·⊖][Na⊕(DME)3]". Zeitschrift für Naturforschung B 49, n.º 10 (1 de outubro de 1994): 1339–47. http://dx.doi.org/10.1515/znb-1994-1007.

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AbstractThe one-electron transfer to large π-delocalized hydrocarbons provides an interesting possibility to crystallize solvent-separated ion-pair salts containing optimally solvated cations. Accordingly, the reduction of 9.9′-bianthryl in aprotic 1.2-dimethoxyethane (DME) solution at a sodium metal mirror allows to grow dark blue, brick-like crystals of its radical anion and threefold DME-solvated sodium cation. The structure of the radical anion is very similar to that recently published for the neutral molecule. According to AM 1 enthalpy hypersurface calculations based on the structural data, the torsion angle between 60° and 120° is determined by the lattice packing and the negative charge is -π-delocalized predominantly within only one anthracene subunit. The counter cation [Na⊕(DME)3], reported only three times so far, shows a sixfold propeller-like coordination of approximate D3 skeletal symmetry with contact distances Na⊕···O between 232 and 243 pm and angles ≮ONa⊕O varying between 69° and 159°. Due to the small repulsion between the chelating DME molecules, the isodesmically calculated Na⊕ solvation enthalpy is more negative than that of the analogous tetrahydrofuran complex [Na⊕(THF)6] - as confirmed by the laboratory experience that salts of less stable anions are preferentially crystallized from a strongly cation solvating DME solution.

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Tachikawa, Hiroto, Anders Lund e Masaaki Ogasawara. "A model calculation on structures and excitation energies of the hydrated electron". Canadian Journal of Chemistry 71, n.º 1 (1 de janeiro de 1993): 118–24. http://dx.doi.org/10.1139/v93-017.

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Model calculations were made on the hydrated electron by using the ab initio MO method combined with the MR-SD-Cl method and the coupled cluster theory. The models used in the calculations were water clusters denoted by [e−(H2O)n(H2O)m], where n = 2,3,4, and 6 for the first solvation shell and m = 0–28 for the second and third solvation shells. In these model calculations, the interactions between the excess electron and the water molecules in the first solvation shell are explicitly calculated by ab initio MO methods and the water molecules in the second and third solvation shells were represented by the fractional charges obtained at the MP2/D95V** level. The stabilization energies and the solvation radius r(e−–O), in terms of the distance between the center of the cavity and an oxygen atom of the surrounding water molecules, increased monotonically with the number of water molecules in the first solvation shell. On the other hand, the first excitation energy was not dependent on the number of water molecules in solvation shells, but constant, with the value of ca. 2.0 eV. On the basis of the present calculations, we suggest that (1) the energetic stability of excess electrons depends on both short-range interaction and long-range interaction, (2) the first excitation energy is critically affected by only the short-range interactions, and the excitation is theoretically attributed to the1s→2p transition of the excess electron.

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Hadizadeh, Mohammad Hassan, Lewen Yang, Guoyong Fang, Zongyang Qiu e Zhenyu Li. "The mobility and solvation structure of a hydroxyl radical in a water nanodroplet: a Born–Oppenheimer molecular dynamics study". Physical Chemistry Chemical Physics 23, n.º 27 (2021): 14628–35. http://dx.doi.org/10.1039/d1cp01830b.

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48

Chen, Wei-Lin, e Shiang-Tai Lin. "Explicit consideration of spatial hydrogen bonding direction for activity coefficient prediction based on implicit solvation calculations". Physical Chemistry Chemical Physics 19, n.º 31 (2017): 20367–76. http://dx.doi.org/10.1039/c7cp02317k.

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FAINBERG, B. D., B. ZOLOTOV e D. HUPPERT. "NONLINEAR LASER SPECTROSCOPY OF NONLINEAR SOLVATION". Journal of Nonlinear Optical Physics & Materials 05, n.º 04 (outubro de 1996): 789–807. http://dx.doi.org/10.1142/s0218863596000568.

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In this study we show that the transient four-photon spectroscopy with pulses longer than the electronic transition dephasing can be used for nonlinear solvation study, i.e., when the linear response for the solvation dynamics breaks down. We have obtained new formulae describing the time evolution of the moments of the nonlinear optical spectra and, in particular, the time resolved fluorescence in the case of nonlinear solvation.

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50

Hidayat, Yuniawan, Ria Armunanto e Harno Dwi Pranowo. "QMCF-MD Simulation and NBO Analysis of K(I) Ion in Liquid Ammonia". Indonesian Journal of Chemistry 18, n.º 2 (30 de maio de 2018): 203. http://dx.doi.org/10.22146/ijc.26788.

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Ab initio of Quantum Mechanics Charge Field Molecular Dynamic (QMCF-MD) of K(I) ion in liquid ammonia has been studied. A Hartree-Fock level of theory was coupled with LANL2DZ ECP basis set for K(I) ion and DZP (Dunning) for ammonia. Two regions as first and second solvation shell were observed. In the first solvation shell at distance 3.7 (Å), K(I) ion was coordinated by four to eight ammonia molecules dominated by K(NH3)6+ species. Second shell of solvation was ranging between 3.7 Å to 7.3 Å. Within simulation time of 20 ps, the frequent exchange processes of ligands indicating for a very labile solvation structure. Four mechanism types of ligand exchange between first and second solvation shell were observed. Mean residence time of ligand is less than 2 ps confirming weak in ion-ligand interaction. Evaluation of K(NH3)6+ using natural bond orbital analysis shows that the Wiberg bond Index is less than 0.05 indicating weak electrostatic interaction of K-N.

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