Multiple nucleation pathways near triple points of Ar–Kr mixtures

Abstract

Cluster partition functions for droplets of Ar–Kr mixtures are evaluated at 90 and 120 K by the inversely restricted sampling (IRS) algorithm. These quantities and series expansion techniques are used within the droplet model to condensation to predict the condensation curve in the neighborhood of a triple point of the Ar–Kr phase diagrams. Using the same series, the free energy surface for droplet growth is examined for supersaturated states of the mixture. For strongly supersaturated states in the neighborhood of the triple point, we find two saddle-point free energy barriers. It is suggested that these physical circumstances provide a sensitive testing ground for molecular theories of homogeneous nucleation.