Thermodynamic properties for the triangular-well fluid

Abstract

Abstract The thermodynamic properties of the triangular-well fluid with a well range of up to twice the hard sphere diameter were studied by means of a new developed equation of state and molecular simulation. This EoS is based on the perturbation theory of Barker and Henderson with the first and second-order perturbation terms evaluated by molecular simulation and then a fit with a simple function based on the radial distribution function of the reference fluid. The thermodynamic properties for the triangular-well fluid were also obtained directly by Gibbs ensemble and NPT Monte Carlo simulations. Good agreement is observed between the proposed EoS and the molecular simulation results. A model for the triangular-well solid is also presented; this has been used to calculate the solid–liquid transition line. Very good agreement is obtained with previously report values for this line and for the triple point temperature and pressure. Keywords: Triangular-well potentialMonte Carlo simulationPerturbation theoryVapour–liquidSolid–fluid Acknowledegements The authors thank CONACYT and IPN for their financial support. Thanks are given to Professor D.A. Kofke and Professor J. Adhikari for sending us their simulation data for triangular-well fluid. Thanks are given to Intel Co. for grant us a non-commercial/academic license for their Fortran compiler for Linux