The solubility of oxygen in n-hexane and in n-perfluorohexane was determined experimentally and calculated by computer simulation. A precision apparatus based on a saturation method at constant pressure was used to measure the solubility at temperatures from 288 to 313 K and close to atmospheric pressure. Henry's law coefficients, H 2,1 (T,p sat 1 ), were obtained from the experimental data and their temperature dependence was represented by appropriate correlations. The precision of the results was characterised by average deviations of H 2,1 from these smoothing equations and is of AE0.5% and AE0.8% for oxygen in n-hexane and in n-perfluorohexane, respectively. From the temperature variation of the Henry's law coefficients, partial molar solvation quantities such as the variation of the Gibbs energy, enthalpy and entropy were derived. Molecular dynamics simulations with all-atom force fields, associated with Widom's test particle insertion method, were used to calculate the residual chemical potential of oxygen in the two solvents studied leading to Henry's law coefficients which were then compared to the experimental values. The difference between oxygen solubility in the two solvents was interpreted on the basis of solute-solvent interactions and structural properties such as solute-solvent radial distribution functions.

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The solubility of xenon in n-hexane and n-perfluorohexane has been studied using both molecular simulation and a version of the SAFT approach (SAFT-VR). The calculations were performed close to the saturation line of each solvent, between 200K and 450K, which exceeds the smaller temperature range where experimental data are available in the literature. Molecular dynamics simulations, associated with Widom's test particle insertion method, were used to calculate the residual chemical potential of xenon in n-hexane and nperfluorohexane and the corresponding Henry's law coefficients. The simulation results overestimate the solubility of xenon in both solvents when simple geometric combining rules are used, but are in good agreement if a binary interaction parameter is,included. With the SAFT-VR approach we are able to reproduce the experimental solubility for xenon in n-hexane, using simple Lorenk-Ekrthelot rules to describe the unlike interaction. In the case of nperfluorohexane as a solvent, a binary interaction parameter was introduced, taken from previous work on (xe + C2Fs) mixtures. Overall, good agreement is obtained between the simulation, theoretical and experimental data.

The solubility of hexafluoroethane in water was determined experimentally and, together with that of tetrafluoromethane, calculated by molecular simulation. A high-precision apparatus based on an extraction method was used to measure the solubility of hexafluoroethane in water in the temperature range of 287-328 K at pressures close to atmospheric. The experimental data obtained were used to calculate Henry's law coefficients H 2,1 (p 1 sat ,T), whose temperature dependence was represented by appropriate correlations. The imprecision of the results was characterized by average deviations of H 2,1 from these smoothing equations and is of (0.17%. From the temperature variation of the Henry's law coefficients, partial molar solution quantities such as the variation of the Gibbs energy, enthalpy, entropy, and heat capacity were derived. Monte Carlo simulations, associated with Widom's test particle insertion method and the finite-difference thermodynamic integration technique, were used to calculate the residual chemical potential of low molecular weight alkanes and perfluoroalkanes in water leading to Henry's law coefficients. Simulations were performed from 280 to 500 K along the saturation line of the pure solvent. The simulation method was validated by the calculation of H 2,1 (p 1 sat ,T) for methane and ethane in water for which quantitative predictions were attained even at the lowest temperatures. The calculations for tetrafluoromethane and hexafluoroethane in water were compared with experimental values, when available, to test intermolecular potential models. Solute-solvent radial distribution functions were obtained from simulation at low and high temperatures.