Prediction of Phase Separation Using a Modified Regular Solution Theory and the SMD Continuum Solvation Model

Abstract

It is proposed a new expression for the β parameter in the regular solution theory, using the solvation free energy concept instead of the solubility parameter. This modified regular solution theory can be applied for any liquid mixture combined with any method for solvation free energy calculation. The new approach was tested in fifteen liquid mixtures using the solvation model density (SMD) continuum solvation model and has successfully predicted the phase behavior, with exception of water-acetonitrile mixture. This flaw can be attributed to the microheterogeneity of this system. The main advantage of the present approach is a fast prediction of phase separation. ]]>

Hybrid discrete‐continuum solvation methods

“…The solvent assisted process is favored but the energy barrier fluctuates over a range of 4 kcal/mol with additional waters whereas the activation energy for the substrate-assisted mechanism decreases with the number of explicit solvent molecules. For MeP, the transition state energy associated with the addition step of water in the substrate assisted pathway is calculated to decrease with an increasing number of explicit solvent molecules (1)(2)(3)(4)(5)(6)(7)(8). The general conclusion for these two cases is that the mechanistic and energetics information obtained from hybrid calculations is significant and far superior to that obtained from a pure continuum model.…”

“…As examples, acid–base equilibrium depends on the solvent and it is possible to modulate the acidity by changing the solvent . Solvent effects in chemical reactions are critical to reach high product yield and even phase equilibria can be formulated via solvation thermodynamic concepts . The importance of solvation in chemical reactions is known since the 19th century and has long attracted the attention of theoretical chemists .…”

Estimation of Solvation Quantities from Experimental Thermodynamic Data: Development of the Comprehensive CompSol Databank for Pure and Mixed Solutes

“…In such a case, it is assumed that g ' i ðT; PÞ is measured using an ebulliometer, so that at infinite dilution the total pressure is close to the solvent vapor pressure P sat j ðTÞ. In such a case, r pure j;liq ðT; PÞ / r sat j;liq ðTÞ (25) (assumption A1) and…”

“…As a first illustration, Pliego has shown how Gibbs energies of solvation can be incorporated into the Scatchard-Hildebrand activity-coefficient model to predict liquid-liquid phase equilibria. 25 As another illustration, Hsieh and Lin have introduced Gibbs energies of solvation in the attractive-parameter expression of the Peng-Robinson cubic equation of state (EoS). [26][27][28] The COSMO-SAC solvation model was used to generate Gibbs energies of solvation.…”

CMIRS Solvation Model for Methanol: Parametrization, Testing, and Comparison with SMD, SM8, and COSMO-RS

“…The interaction of molecules and ions with the solvent is a very important phenomenon, which is quantified by the solvation free energy. − This property directly translates into the chemical potential of the solute; it is related to many different equilibria in the condensed phase, like acid dissociation constants (p K a ), − reduction potentials, , partition coefficients, phase equilibria and solubility, − small molecule–protein interaction or host–guest complexes, and the most diverse kinds of chemical equilibria and kinetics processes. − Therefore, an accurate calculation of the solvation free energy is of paramount importance for theoretical and computational chemistry when dealing with systems of technical interest . This fact has motivated the development of a wide variety of theoretical approaches for computing the solvation free energy.…”