GC-MOSCED: A group contribution method for predicting MOSCED parameters with application to limiting activity coefficients in water and octanol/water partition coefficients

Abstract

The MOdified Separation of Cohesive Energy Density (MOSCED) is a solubility parameter based method that can both quantitatively predict limiting activity coefficients and can additionally be used to qualitatively understand the underlying molecular-level interactions for intuitive solvent selection and formulation. However, before predictions may be made, MOSCED parameters must be available. Here we propose a group contribution method (GC-MOSCED) to predict parameters devoid of experimental data. Predictions of limiting activity coefficients in water and octanol/water partition coefficients made using GC-MOSCED are found to be in close agreement with MOSCED using existing parameters. We additionally propose a relation between MOSCED parameters and enthalpy of vaporization, and demonstrate the ability of GC-MOSCED to predict enthalpy of vaporization. An interactive software suite has also been developed to facilitate the calculation of GC-MOSCED parameters.