Statistical thermodynamics of liquids using the Monte Carlo method. II. Liquid chloroform.

Thermodynamic properties and radial distribution functions for liquid chloroform were calculated using the Monte Carlo method implemented with Metropolis algorithm in the NpT ensemble at 298 K and 1 atm, A five site model was developed to represent the chloroform molecules. A force field composed by Lennard-Jones and Coulomb potential functions was used to calculate the intermolecular energy. The partial charges needed to represent the Coulombic interactions were obtained from quantum chemical ab initio calculations, The Lennard-Jones parameters were adjusted to reproduce experimental values for density and enthalpy of vaporization for pure liquid, All thermodynamic results are in excellent agreement with experimental data, The correlation functions calculated are in good accordance with theoretical results available in the literature. The free energy for solvating one chloroform molecule into its own liquid st 298 IC and 1 atm was computed as an additional test of the potential model. The result obtained compares well with the experimental value. The medium effects an cis/trans convertion of a hypotetical solute in water TIP4P and chloroform solvents were also accomplished. The results obtained from this investigation are in agreement with estimates of the continuous theory of solvation.