Enhanced kinetics and free-volume universality in dense aggregating systems

Abstract

Aggregation kinetics and cluster-size distributions are studied with off-lattice, diffusion-limited cluster-cluster simulations. With increased cluster crowding (occurring at late times) as measured by the normalized free volume, Ω, both the kinetics speeds up and the size distribution broadens. The exponents characterizing each, z and λ, respectively, are found to be universal functions of Ω. Moreover, the relation z=(1-λ)-1 continues to hold up to Ω=0 (the ideal gel point), implying mean-field kinetics still applies despite the crowding.