Thermodynamics of a miscibility gap system and a test of nucleation theory

Abstract

In an earlier paper an attempt was made to perform a critical test of nucleation theory for condensed systems using the miscibility gap system methylcyclohexane + perfluoromethylcyclohexane (C₇H₁₄+C₇F₁₄) and the equation for the thermodynamic free energy of mixing derived by Dyke, Rowlinson and Thacker from their vapour pressure measurements. Because these equations are not fully consistent with the phase diagram it was necessary to modify them in an arbitrary manner for application to the nucleation problem. A more complete analysis of the vapour pressure data of Dyke et al. has now been performed. The newly-derived free energies of mixing are sufficiently consistent with the phase diagram that no correction need be applied. Using these new free-energy-of mixing functions in the test of nucleation theory leads to the same conclusion as reached earlier, i.e., verification of the corrected nucleation theory.