Subcritical and supercritical thermodynamic properties calculations for quantum light molecules using an extended LJ potential-based equation of state

Abstract

In this work, the extended Lennerd-Jones potential-based equation of state (ELJ-based EoS) on which the effective near-neighbour pair interactions are LJ (12,6,3) type has been extended to predict the density and other thermodynamic properties of quantum light molecules in subcritical (liquid) and supercritical regions. There are no upper and lower density limitations in the applicability of the model for these systems. Having the temperature dependence of the parameters of new EoS, the parameters can be determined at any temperature for each of quantum light molecules, including H2, p-H2, D2, He, and Ne. A comparison with literature data has been made. The results show that the ELJ-based EoS can be used to predict the density and other thermodynamic properties of quantum light molecules within experimental errors. The average absolute deviations for density are better than 0.2% in the subcritical region and 0.12% in the supercritical region for all studied molecules. © 2013 © 2013 Taylor & Francis.