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Boris N Solomonov - One of the best experts on this subject based on the ideXlab platform.
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thermodynamic description of the Solvophobic effect in ionic liquids
Fluid Phase Equilibria, 2016Co-Authors: Igor A Sedov, Boris N SolomonovAbstract:Abstract The Solvophobic effect is a driving force for self-assembly processes that acts in protic molecular organic solvents as well as in both protic and aprotic ionic liquids. It is known to reduce the solubility of apolar compounds and influence the magnitudes of thermodynamic functions of solvation in molecular solvents. In ionic liquids, thermodynamic aspects of the Solvophobic effects have not yet been carefully considered. By comparing the relations between the Gibbs free energy and enthalpy of solvation of different compounds, we show that the Solvophobic effect in aprotic ionic liquids can be even stronger than in organic solvents forming a network of intermolecular hydrogen bonds, such as formamide and ethylene glycol. The strength of the Solvophobic effect expressed in terms of energy contributions is correlated with the average number of ions per unit volume, which is inversely proportional to the molar volume of the liquid. It is shown that the Solvophobic effects become stronger when we change the cation or anion of the ionic liquid with another of a smaller size, and can be extremely weak when the cation contains long alkyl chains, but they are a general phenomenon for all ionic liquids.
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standard molar gibbs free energy and enthalpy of solvation of low polar solutes in formamide derivatives at 298k
Thermochimica Acta, 2016Co-Authors: Igor A Sedov, Mikhail A Stolov, Timur Magsumov, Boris N SolomonovAbstract:Abstract Novel experimental values of the limiting activity coefficients and standard molar enthalpies of solution in N-methylformamide at 298.15 K are reported and used to calculate the thermodynamic functions of solvation. We compare the plots of the standard molar Gibbs free energy against the standard molar enthalpy of solvation of low polar molecules in N-methylformamide, N,N-dimethylformamide, and formamide. The Solvophobic effect is responsible for the deviations of the data points from the straight line corresponding to a correlation between thermodynamic functions of solvation in aprotic solvents. It is shown that the Solvophobic effects are strong in formamide solutions, significantly weaker in N-methylformamide, and very weak in N,N-dimethylformamide, which coincides with the average number of intermolecular hydrogen bonds per unit volume of these solvents. Behavior of solutions in binary solvents composed of N-methylformamide or formamide mixed with water and ethylene glycol and a possibility to tune the Solvophobic effect by changing the solvent composition are also considered.
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tert butyl chloride as a probe of the Solvophobic effects
Fluid Phase Equilibria, 2014Co-Authors: Igor A Sedov, Mikhail A Stolov, Boris N SolomonovAbstract:Abstract Relationships between the Gibbs free energy and enthalpy of solvation of tert -butyl chloride in various protic solvents are considered in order to compare the strength of the Solvophobic effects from solvent to solvent. The values of thermodynamic functions of solvation are determined experimentally using titration calorimetry and gas chromatographic headspace analysis techniques. Positions of the data points on the Δ G vs Δ H plot indicate that the Solvophobic effects take place in various mono- and dihydric alcohols, acetic acid, and acid amides. The excess positive contribution into free energy of solvation of tert -butyl chloride in self-associated solvents is used to characterize their strength quantitatively. It is shown that the Solvophobic effects are stronger when the concentration of the hydrogen bonds in a solvent is larger.
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enthalpies and gibbs free energies of solvation in ethylene glycol at 298 k influence of the Solvophobic effect
Fluid Phase Equilibria, 2013Co-Authors: Igor A Sedov, Mikhail A Stolov, Boris N SolomonovAbstract:Abstract Enthalpies of solution of low-polar substances: aliphatic and aromatic hydrocarbons, including alkanes, cycloalkanes, alkylbenzenes, naphthalene, biphenyl, and halobenzenes in ethylene glycol were measured at temperature T = 298.15 K using semi-adiabatic solution calorimetry. For some of these systems, previously unknown values of limiting activity coefficients were also determined using GC headspace analysis. Consideration of compensation plots of the Gibbs free energy vs enthalpy of solvation shows that the behavior of solutions in ethylene glycol is different from that of solutions in non-associated aprotic solvents. The Gibbs energies of solvation are significantly increased relative to the enthalpies, which is the sign of the Solvophobic effect. The contribution of the Solvophobic effect into the Gibbs energies of solvation of various substances was quantified using an extrathermodynamic approach. A linear correlation between this quantity and a molecular volume of dissolved compound was found. The Solvophobic effect in ethylene glycol is stronger than in monohydric alcohols, weaker than in formamide and much weaker than in water. It is also entropy-driven and does not affect the enthalpies of solution of the studied substances in ethylene glycol.
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thermodynamics of solvation and Solvophobic effect in formamide
SCOPUS00219614-2013-64-SID84878703339, 2013Co-Authors: Igor A Sedov, Mikhail A Stolov, Boris N SolomonovAbstract:Using semi-adiabatic calorimetry, we measured the enthalpies of solution for various low-polar compounds including alkanes, aromatic hydrocarbons and their halogenated derivatives in formamide at temperature of 298 K. For the same compounds, the values of limiting activity coefficients in formamide were determined using GC headspace analysis at 298 K, and Gibbs free energies of solution and solvation were calculated. Based on these data and the available literature values of the Gibbs free energy of solvation in formamide for a number of other low-polar solutes, a study of the Solvophobic effect in this solvent is performed, and its resemblance to the hydrophobic effect in aqueous solutions is demonstrated. It is shown that the contribution of the Solvophobic effect into the solvation Gibbs free energy in formamide is much higher than that in aliphatic alcohols, but lower than that in water. Like in water, the magnitude of this contribution for different solutes linearly increases with the solute molecular volume. Solvophobic effect also significantly affects the enthalpies of dissolution in formamide, causing them to be more negative in the case of alkanes and more positive in the case of arenes.
Igor A Sedov - One of the best experts on this subject based on the ideXlab platform.
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thermodynamic description of the Solvophobic effect in ionic liquids
Fluid Phase Equilibria, 2016Co-Authors: Igor A Sedov, Boris N SolomonovAbstract:Abstract The Solvophobic effect is a driving force for self-assembly processes that acts in protic molecular organic solvents as well as in both protic and aprotic ionic liquids. It is known to reduce the solubility of apolar compounds and influence the magnitudes of thermodynamic functions of solvation in molecular solvents. In ionic liquids, thermodynamic aspects of the Solvophobic effects have not yet been carefully considered. By comparing the relations between the Gibbs free energy and enthalpy of solvation of different compounds, we show that the Solvophobic effect in aprotic ionic liquids can be even stronger than in organic solvents forming a network of intermolecular hydrogen bonds, such as formamide and ethylene glycol. The strength of the Solvophobic effect expressed in terms of energy contributions is correlated with the average number of ions per unit volume, which is inversely proportional to the molar volume of the liquid. It is shown that the Solvophobic effects become stronger when we change the cation or anion of the ionic liquid with another of a smaller size, and can be extremely weak when the cation contains long alkyl chains, but they are a general phenomenon for all ionic liquids.
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standard molar gibbs free energy and enthalpy of solvation of low polar solutes in formamide derivatives at 298k
Thermochimica Acta, 2016Co-Authors: Igor A Sedov, Mikhail A Stolov, Timur Magsumov, Boris N SolomonovAbstract:Abstract Novel experimental values of the limiting activity coefficients and standard molar enthalpies of solution in N-methylformamide at 298.15 K are reported and used to calculate the thermodynamic functions of solvation. We compare the plots of the standard molar Gibbs free energy against the standard molar enthalpy of solvation of low polar molecules in N-methylformamide, N,N-dimethylformamide, and formamide. The Solvophobic effect is responsible for the deviations of the data points from the straight line corresponding to a correlation between thermodynamic functions of solvation in aprotic solvents. It is shown that the Solvophobic effects are strong in formamide solutions, significantly weaker in N-methylformamide, and very weak in N,N-dimethylformamide, which coincides with the average number of intermolecular hydrogen bonds per unit volume of these solvents. Behavior of solutions in binary solvents composed of N-methylformamide or formamide mixed with water and ethylene glycol and a possibility to tune the Solvophobic effect by changing the solvent composition are also considered.
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tert butyl chloride as a probe of the Solvophobic effects
Fluid Phase Equilibria, 2014Co-Authors: Igor A Sedov, Mikhail A Stolov, Boris N SolomonovAbstract:Abstract Relationships between the Gibbs free energy and enthalpy of solvation of tert -butyl chloride in various protic solvents are considered in order to compare the strength of the Solvophobic effects from solvent to solvent. The values of thermodynamic functions of solvation are determined experimentally using titration calorimetry and gas chromatographic headspace analysis techniques. Positions of the data points on the Δ G vs Δ H plot indicate that the Solvophobic effects take place in various mono- and dihydric alcohols, acetic acid, and acid amides. The excess positive contribution into free energy of solvation of tert -butyl chloride in self-associated solvents is used to characterize their strength quantitatively. It is shown that the Solvophobic effects are stronger when the concentration of the hydrogen bonds in a solvent is larger.
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enthalpies and gibbs free energies of solvation in ethylene glycol at 298 k influence of the Solvophobic effect
Fluid Phase Equilibria, 2013Co-Authors: Igor A Sedov, Mikhail A Stolov, Boris N SolomonovAbstract:Abstract Enthalpies of solution of low-polar substances: aliphatic and aromatic hydrocarbons, including alkanes, cycloalkanes, alkylbenzenes, naphthalene, biphenyl, and halobenzenes in ethylene glycol were measured at temperature T = 298.15 K using semi-adiabatic solution calorimetry. For some of these systems, previously unknown values of limiting activity coefficients were also determined using GC headspace analysis. Consideration of compensation plots of the Gibbs free energy vs enthalpy of solvation shows that the behavior of solutions in ethylene glycol is different from that of solutions in non-associated aprotic solvents. The Gibbs energies of solvation are significantly increased relative to the enthalpies, which is the sign of the Solvophobic effect. The contribution of the Solvophobic effect into the Gibbs energies of solvation of various substances was quantified using an extrathermodynamic approach. A linear correlation between this quantity and a molecular volume of dissolved compound was found. The Solvophobic effect in ethylene glycol is stronger than in monohydric alcohols, weaker than in formamide and much weaker than in water. It is also entropy-driven and does not affect the enthalpies of solution of the studied substances in ethylene glycol.
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thermodynamics of solvation and Solvophobic effect in formamide
SCOPUS00219614-2013-64-SID84878703339, 2013Co-Authors: Igor A Sedov, Mikhail A Stolov, Boris N SolomonovAbstract:Using semi-adiabatic calorimetry, we measured the enthalpies of solution for various low-polar compounds including alkanes, aromatic hydrocarbons and their halogenated derivatives in formamide at temperature of 298 K. For the same compounds, the values of limiting activity coefficients in formamide were determined using GC headspace analysis at 298 K, and Gibbs free energies of solution and solvation were calculated. Based on these data and the available literature values of the Gibbs free energy of solvation in formamide for a number of other low-polar solutes, a study of the Solvophobic effect in this solvent is performed, and its resemblance to the hydrophobic effect in aqueous solutions is demonstrated. It is shown that the contribution of the Solvophobic effect into the solvation Gibbs free energy in formamide is much higher than that in aliphatic alcohols, but lower than that in water. Like in water, the magnitude of this contribution for different solutes linearly increases with the solute molecular volume. Solvophobic effect also significantly affects the enthalpies of dissolution in formamide, causing them to be more negative in the case of alkanes and more positive in the case of arenes.
Solomonov B. - One of the best experts on this subject based on the ideXlab platform.
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Evaluating the contribution of Solvophobic effects to the gibbs energy of solvation in methanol
2020Co-Authors: Stolov M., Solomonov B.Abstract:A method for analyzing the thermodynamical manifestations of Solvophobic effects is proposed on the basis of considering the relationship between the Gibbs energy and solvation enthalpy of nonelectrolytes. It is demonstrated that, for solutions in nonassociated solvents, there is a linear isoequilibrium dependence between them, and the coefficients of linear dependence are almost equivalent for various dissolved substances and solvents. It is determined that the deviations from this dependence observed in the case of associated solvents are always positive, and the consequences of the manifestations of Solvophobic effects are considered. The contributions from the Solvophobic effect to the Gibbs energy of solvation of various nonpolar compounds in methanol are determined on the basis of a thermodynamic model of solvation suggested earlier. It is shown that in both methanol and aqueous solutions, the values of these contributions correlate linearly with the characteristic molecular volume of the dissolved substance. © Pleiades Publishing, Ltd., 2011
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Thermodynamic description of the Solvophobic effect in ionic liquids
2020Co-Authors: Solomonov B.Abstract:© 2016 Elsevier B.V.The Solvophobic effect is a driving force for self-assembly processes that acts in protic molecular organic solvents as well as in both protic and aprotic ionic liquids. It is known to reduce the solubility of apolar compounds and influence the magnitudes of thermodynamic functions of solvation in molecular solvents. In ionic liquids, thermodynamic aspects of the Solvophobic effects have not yet been carefully considered. By comparing the relations between the Gibbs free energy and enthalpy of solvation of different compounds, we show that the Solvophobic effect in aprotic ionic liquids can be even stronger than in organic solvents forming a network of intermolecular hydrogen bonds, such as formamide and ethylene glycol. The strength of the Solvophobic effect expressed in terms of energy contributions is correlated with the average number of ions per unit volume, which is inversely proportional to the molar volume of the liquid. It is shown that the Solvophobic effects become stronger when we change the cation or anion of the ionic liquid with another of a smaller size, and can be extremely weak when the cation contains long alkyl chains, but they are a general phenomenon for all ionic liquids
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Solvophobic effects: Qualitative determination and quantitative description
2020Co-Authors: Solomonov B.Abstract:Solvophobic effects strongly influence the thermodynamic properties of solutions and are one of the driving forces of self-assembly processes of supramolecular structures. However, the generally accepted definition and a quantitative measure of these effects have so far been absent. Based on the analysis of a large set of experimental data on the thermodynamic functions of solvation in various systems, we propose a qualitative criterion allowing us to judge about whether the Solvophobic effects are manifested in the solution or not, and also a method to determine their contributions to the thermodynamic functions of solvation. A feature of the Solvophobic effect is a violation of the linear relationship between the Gibbs free energy and the enthalpy of solvation, which is fulfilled for the solutions of different compounds in many non-associated solvents. It is shown that in self-associated solvents the Solvophobic effect is observed for any dissolved compounds, including well soluble ones, resulting in an increase in the Gibbs energy of solvation. Previously proposed Solvophobicity parameters are considered and compared with our results. © 2013 I. A. Sedov, B. N. Solomonov
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Solvophobic effects and relationships between the Gibbs energy and enthalpy for the solvation process
2020Co-Authors: Stolov M., Solomonov B.Abstract:An approach is suggested to describe the Solvophobic effects in various solvents, qualitatively and quantitatively. We analyzed the relationships between the Gibbs energies and enthalpies of solvation of alkanes in various solvents on the basis of existing experimental data. It is shown that for a large group of solvents, there is a linear correlation between the two quantities. Other solvents, primarily self-associated, show deviations from this line. These deviations are always positive, leading to a decrease in solubility, and can be used as a measure of the strength of the Solvophobic effects. It is also shown that the Solvophobic effects is not the only factor determining the solubility, even for alkane solutes. The magnitudes of contributions of the Solvophobic effect into the Gibbs energies of solvation of various compounds in monohydric alcohols are determined. These magnitudes are found to be linearly correlated with a characteristic molecular volume of a solute. The slope of correlation grows up with the concentration of hydrogen bonds in the liquid solvent. Copyright © 2011 John Wiley & Sons, Ltd
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Tert-Butyl chloride as a probe of the Solvophobic effects
2020Co-Authors: Stolov M., Solomonov B.Abstract:© 2014 Elsevier B.V. Relationships between the Gibbs free energy and enthalpy of solvation of tert-butyl chloride in various protic solvents are considered in order to compare the strength of the Solvophobic effects from solvent to solvent. The values of thermodynamic functions of solvation are determined experimentally using titration calorimetry and gas chromatographic headspace analysis techniques. Positions of the data points on the δ. G vs δ. H plot indicate that the Solvophobic effects take place in various mono- and dihydric alcohols, acetic acid, and acid amides. The excess positive contribution into free energy of solvation of tert-butyl chloride in self-associated solvents is used to characterize their strength quantitatively. It is shown that the Solvophobic effects are stronger when the concentration of the hydrogen bonds in a solvent is larger
Mikhail A Stolov - One of the best experts on this subject based on the ideXlab platform.
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standard molar gibbs free energy and enthalpy of solvation of low polar solutes in formamide derivatives at 298k
Thermochimica Acta, 2016Co-Authors: Igor A Sedov, Mikhail A Stolov, Timur Magsumov, Boris N SolomonovAbstract:Abstract Novel experimental values of the limiting activity coefficients and standard molar enthalpies of solution in N-methylformamide at 298.15 K are reported and used to calculate the thermodynamic functions of solvation. We compare the plots of the standard molar Gibbs free energy against the standard molar enthalpy of solvation of low polar molecules in N-methylformamide, N,N-dimethylformamide, and formamide. The Solvophobic effect is responsible for the deviations of the data points from the straight line corresponding to a correlation between thermodynamic functions of solvation in aprotic solvents. It is shown that the Solvophobic effects are strong in formamide solutions, significantly weaker in N-methylformamide, and very weak in N,N-dimethylformamide, which coincides with the average number of intermolecular hydrogen bonds per unit volume of these solvents. Behavior of solutions in binary solvents composed of N-methylformamide or formamide mixed with water and ethylene glycol and a possibility to tune the Solvophobic effect by changing the solvent composition are also considered.
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tert butyl chloride as a probe of the Solvophobic effects
Fluid Phase Equilibria, 2014Co-Authors: Igor A Sedov, Mikhail A Stolov, Boris N SolomonovAbstract:Abstract Relationships between the Gibbs free energy and enthalpy of solvation of tert -butyl chloride in various protic solvents are considered in order to compare the strength of the Solvophobic effects from solvent to solvent. The values of thermodynamic functions of solvation are determined experimentally using titration calorimetry and gas chromatographic headspace analysis techniques. Positions of the data points on the Δ G vs Δ H plot indicate that the Solvophobic effects take place in various mono- and dihydric alcohols, acetic acid, and acid amides. The excess positive contribution into free energy of solvation of tert -butyl chloride in self-associated solvents is used to characterize their strength quantitatively. It is shown that the Solvophobic effects are stronger when the concentration of the hydrogen bonds in a solvent is larger.
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enthalpies and gibbs free energies of solvation in ethylene glycol at 298 k influence of the Solvophobic effect
Fluid Phase Equilibria, 2013Co-Authors: Igor A Sedov, Mikhail A Stolov, Boris N SolomonovAbstract:Abstract Enthalpies of solution of low-polar substances: aliphatic and aromatic hydrocarbons, including alkanes, cycloalkanes, alkylbenzenes, naphthalene, biphenyl, and halobenzenes in ethylene glycol were measured at temperature T = 298.15 K using semi-adiabatic solution calorimetry. For some of these systems, previously unknown values of limiting activity coefficients were also determined using GC headspace analysis. Consideration of compensation plots of the Gibbs free energy vs enthalpy of solvation shows that the behavior of solutions in ethylene glycol is different from that of solutions in non-associated aprotic solvents. The Gibbs energies of solvation are significantly increased relative to the enthalpies, which is the sign of the Solvophobic effect. The contribution of the Solvophobic effect into the Gibbs energies of solvation of various substances was quantified using an extrathermodynamic approach. A linear correlation between this quantity and a molecular volume of dissolved compound was found. The Solvophobic effect in ethylene glycol is stronger than in monohydric alcohols, weaker than in formamide and much weaker than in water. It is also entropy-driven and does not affect the enthalpies of solution of the studied substances in ethylene glycol.
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thermodynamics of solvation and Solvophobic effect in formamide
SCOPUS00219614-2013-64-SID84878703339, 2013Co-Authors: Igor A Sedov, Mikhail A Stolov, Boris N SolomonovAbstract:Using semi-adiabatic calorimetry, we measured the enthalpies of solution for various low-polar compounds including alkanes, aromatic hydrocarbons and their halogenated derivatives in formamide at temperature of 298 K. For the same compounds, the values of limiting activity coefficients in formamide were determined using GC headspace analysis at 298 K, and Gibbs free energies of solution and solvation were calculated. Based on these data and the available literature values of the Gibbs free energy of solvation in formamide for a number of other low-polar solutes, a study of the Solvophobic effect in this solvent is performed, and its resemblance to the hydrophobic effect in aqueous solutions is demonstrated. It is shown that the contribution of the Solvophobic effect into the solvation Gibbs free energy in formamide is much higher than that in aliphatic alcohols, but lower than that in water. Like in water, the magnitude of this contribution for different solutes linearly increases with the solute molecular volume. Solvophobic effect also significantly affects the enthalpies of dissolution in formamide, causing them to be more negative in the case of alkanes and more positive in the case of arenes.
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evaluating the contribution of Solvophobic effects to the gibbs energy of solvation in methanol
Russian Journal of Physical Chemistry A, 2011Co-Authors: Igor A Sedov, Mikhail A Stolov, Boris N SolomonovAbstract:A method for analyzing the thermodynamical manifestations of Solvophobic effects is proposed on the basis of considering the relationship between the Gibbs energy and solvation enthalpy of nonelectrolytes. It is demonstrated that, for solutions in nonassociated solvents, there is a linear isoequilibrium dependence between them, and the coefficients of linear dependence are almost equivalent for various dissolved substances and solvents. It is determined that the deviations from this dependence observed in the case of associated solvents are always positive, and the consequences of the manifestations of Solvophobic effects are considered. The contributions from the Solvophobic effect to the Gibbs energy of solvation of various nonpolar compounds in methanol are determined on the basis of a thermodynamic model of solvation suggested earlier. It is shown that in both methanol and aqueous solutions, the values of these contributions correlate linearly with the characteristic molecular volume of the dissolved substance.
Sheshanath V Bhosale - One of the best experts on this subject based on the ideXlab platform.
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Solvophobic control aggregation induced emission of tetraphenylethene substituted naphthalene diimide via intramolecular charge transfer
RSC Advances, 2015Co-Authors: Anushri Rananaware, Sheshanath V BhosaleAbstract:Two new tetraphenylethene-core-substituted naphthalene diimides (TPE-cNDI) were synthesized through linking one and two TPE, where TPE acts both as an electron-donor for ICT and also display the characteristic of AIE effect, i.e. is non-emissive in solution but has enhanced red-emission in both the aggregated and the solid state with high quantum efficiency. Furthermore, both the derivatives self-assembled into variety of nano- to micro-structures via Solvophobic control.
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Solvophobic control of core substituted naphthalene diimide nanostructures
Chemical Communications, 2010Co-Authors: Sheshanath V Bhosale, Chintan Hemant Jani, Cecilia Lalander, Steven J LangfordAbstract:The requirements for the self-assembly of 2,3-annulated core-substituted NDIs into discrete worm-like nanostructures are explored in MeOH–CHCl3 solutions. AFM was used to visualize and characterize the structures formed at precise proportions of solvent mixes.
