Theory of homogeneous nucleation: A chemical kinetic view

In classical theory of homogeneous nucleation the flux is derived initially as a function of rate constants for the condensation and vaporization reactions of clusters in the kinetic path. The evaluation of the vaporization rate for clusters of different size is provided by the Thomson–Gibbs relation. In view of discrepancies still existing between measurements and theoretical predictions and the continuing reservations on applying TG relation to microscopic size clusters a different approach is proposed in the present work. A simple function with two undetermined parameters has been used in place of the TR relation to relate the activation energy of the vaporization reaction to cluster size. The parameters are iterated to assume optimum values in numerical computation so experimental data may be correlated. Calculations show this approach closely predicts and correlates available data for water, benzene, and ethanol. The nucleation formulism is redeveloped with an emphasis on the chemical kinetic view. Surface tension of the liquid and free energy of droplet formation are not used in its derivation.