Monte Carlo simulation of particle aggregation and gelation: I. Growth, structure and size distribution of the clusters.

Lattice and off-lattice Monte Carlo simulations of diffusion-limited cluster aggregation and gelation were done over a broad range of concentrations. The large-scale structure and the size distribution of the clusters are characterized by a crossover at a characteristic size (). For, they are the same as obtained in a dilute DLCA process and forthey are the same as obtained in a static percolation process.is determined by the overlap of the clusters and decreases with increasing particle concentration. The growth rate of large clusters is a universal function of time reduced by the gel time. The large-scale structural and temporal properties are the same for lattice and off-lattice simulations. The average degree of connectivity per particle in the gels formed in off-lattice simulations is independent of the concentration, but its distribution depends on the concentration. [ABSTRACT FROM AUTHOR]