Coarse-Grained Model for Perfluorocarbons and Phase Equilibrium Simulation of Perfluorocarbons/CO2 Mixtures

Abstract

A coarse-grained (CG) model for perfluorocarbons (PFCs) with arbitrary chain length has been established in this work. The construction of the CG model is based on the all-atomic (AA) simulation results and the thermodynamics experimental data. The intramolecular parameters are obtained through reproducing the intramolecular bond and angle distributions from AA simulations. The intermolecular parameters are determined by fitting the experimental bulk densities and surface tensions. Comparison between the CG and AA simulations has confirmed that the CG model can reasonably represent the structure behavior of PFCs. Furthermore, the CG model has been also extended to simulate the vapor−liquid phase equilibria for the mixture of PFCs and carbon dioxide by using the Gibbs ensemble Monte Carlo (GEMC) method. As compared with the experimental data, the GEMC simulation based on the CG model satisfactorily reproduces the mixture phase equilibria. The developed CG model will be useful in simulating the self-assembl...