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Pair configurations to molecular activity coefficients: PAC-MAC

This thesis provides an overview of the development of the Pair Configuration to Molecular Activity Coefficient (PAC-MAC) model.

A.J.M. Sweere
14 June 2017
Thesis in Leiden Repository

PAC-MAC is a computational method to predict thermodynamic miscibility properties of various molecular solutions. Examples of calculated thermodynamic miscibility properties are vapor-liquid equilibrium (VLE) diagrams, mixing free energies and Flory-Huggins χ-interaction parameters. Within PAC-MAC, a unique approach is used by combining the quasi-chemical approximation of Guggenheim with the use of classical force fields. The quasi-chemical approximation is used in foregoing models for miscibility prediction (UNIFAC, COSMO-RS) whereas classical force fields are used in methods preserving the molecular 3D structure (molecular dynamics and Monte Carlo simulations). The combination of the quasi-chemical approximation with classical force fields results in a quick and accurate method containing, besides the force field parameters, only two empirically optimized parameters.