Studies on the freezing of pure liquids - II. The kinetics of homogeneous nucleation in supercooled liquids

Abstract

A modified form of Turnbull & Fisher’s equation for the rate of nueleation in pure liquids is derived from the more general solution of Frenkel to the non-equilibrium steady -state kinetic problem . Recent developments in relaxation theory, based on the Zeldovich— Frenkel formulation of the time-dependent flow of embryos over the size variable g, show that under certain conditions the nucleation time lag may be exceedingly sensitive to the initial state of the condensing system. Frisch’s integral for the nucleation time lag is evaluated for two initial distributions of embryo size. The results, which are of general form, are used to derive expressions for the time lag in supercooled liquids. Methods are given for estimating certain parameters required in the computation of time lags in supercooled liquids.