FLUID PHASE EQUILIBRIA, cilt.236, ss.25-41, 2005 (SCI-Expanded)
A combined study by quantum chemistry and Monte Carlo simulation is conducted to extend the anisotropic united atoms (AUA) intermolecular potential to alkylamines, alkylamides and alkanols. Ab initio simulations are used to derive electrostatic point charges of the investigated molecules. The amplitude and location of these charges are optimized to best reproduce the electrostatic field around the molecule. The Lennard-Jones parameters of the amine -NH2 and alcohol -OH groups are regressed to match the vapor-liquid equilibrium properties of methylamine, propylamine, methanol and ethanol. The Lennard-Jones parameters of the CH2 and CH3 groups are taken from previously published work [P. Ungerer, C. Beauvais, J. Delhommelle, A. Boutin, B. Rousseau, A.H. Fuchs, Optimization of the anisotropic united atoms intermolecular potential for n-alkanes, J. Chem. Phys. 112 (2000) 5499-55].