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In order to understand the role of fluorination on the interactions and partitioning of alcohols in aqueous and organic environments, isobaric-isothermal ensemble Monte Carlo simulations are used to determine environmental predictors, such as free energies of hydration and solvation in 1-octanol and n-hexadecane. Calculations are performed with the united-atom Transferable Potentials for Phase Equilibria (TraPPE) force field and compared against available experimental data. TraPPE was found to provide reliable qualitative predictions of trends with respect to the effect of fluorination on partitioning. Investigation of the local solvation environment around the hydroxyl group reveals that fluorination of carbons closest to the hydroxyl group has the greatest effect on solvation free energies for alcohols in water, 1-octanol and n-hexadecane.

Grand canonical histogram-reweighting Monte Carlo simulations were used to obtain the phase behaviour of several binary mixtures. The main goal of this work was to test the predictive capabilities of recently developed intermolecular potential models that accurately reproduce the phase behaviour of pure components. These united-atom potentials utilize the exponential-6 functional form for repulsive and dispersion interactions and fixed point charges for electrostatic interactions. The mixtures studied were n-pentane—methane, ethane—CO2, propane—CO2, n-pentane-CO2, H2O-ethane, CH3OH-n-hexane and CH3OH-CO2. The conventional Lorentz-Berthelot combining rules, as well as a set of combining rules due to Kong (1973, J. chem. Phys., 59, 2464) were used to obtain unlike-pair potential parameters. The Lorentz—Berthelot rules generally result in more attractive unlike-pair interactions than the Kong rules. For the n-alkane—CO2 systems, predicted phase diagrams are in excellent agreement with experiment when the Kon...