Development of a COSMO-SAC Parametrization with Advanced QM Method TZVPD-FINE

Abstract

Accurate prediction of interactions between compounds is essential for designing advanced materials and industrial processes. COSMO-based models have become prominent tools for estimating phase equilibria in complex systems. In this work, a new COSMO-SAC parametrization is proposed using a more robust quantum mechanical approach: the Becke and Perdew functional with triple-zeta valence polarization with diffuse functions combined with a fine grid marching tetrahedron cavity (BP-TZVPD-FINE). This level of theory enables a refined description of molecular and ionic charge densities. Implemented in JCOSMO software, this parametrization supports input files from TURBOMOLE, improving accessibility for nonexpert users. The model’s performance was evaluated using 6977 experimental data points of infinite-dilution activity coefficients and vapor–liquid and liquid–liquid equilibrium data. Compared with previous parametrization, the new model demonstrated improved accuracy, particularly for systems involving amines, ethers, and dipolar aprotic solvents.