(144a) Application of Low-Pressure Pvt Data for Determining Parameters of the Lennard-Jones Potential-Energy Function Based on the Second Virial Coefficients Data

Thermodynamic properties of any pure substance may be determined by the intermolecular forces existing between the molecules of that substance. Intermolecular forces usually are expressed in terms of potential-energy function. In this paper, parameters of the Lennard-Jones potential-energy function are calculated for some selected molecules by use of the second virial coefficients which are obtained from low-pressure PVT data. The advantage of this method is that the potential-energy parameters, which indicate the microscopic properties of the substance, can be found easily from the macroscopic properties of that substance, i.e. PVT data. The obtained results have considerable accuracy for simple, spherically symmetric molecules. Further, by use of the corresponding-states theory, correlations are made to predict the parameters for other substances, where the obtained results have acceptable accuracy for simple molecules and monatomic gases.