ACCURATE VAPOR-LIQUID-EQUILIBRIUM CALCULATIONS OF SIMPLE FLUIDS

From computer simulation data of 3D Lennard-Jones fluids, we present v ery simple analytical equations of pressure and chemical potential as functions of the temperature and density. By using the standard thermo dynamic procedure of a liquid-vapour equilibrium; i.e. pressure and ch emical potential in the gas phase to be equal to the corresponding val ues in the liquid phase at a given temperature, we have been able to d etermine the vapour-liquid coexistence curve. Despite the simplicity o f our method, we obtain more precise results than those published in t he literature because we use simultaneously both equalities: for press ures and for chemical potentials.