Observation of a flocculation to gel-sol scaling crossover in two-dimensional colloidal aggregation

The pair correlation function of a large connected cluster, formed during the irreversible aggregation of a two-dimensional distribution of colloidal microspheres, shows a distinct crossover from flocculation to gel-sol scaling behaviour consistent with kinetic clustering of cluster model predictions. Smaller isolated clusters arising out of the same aggregation even have lower than expected fractal dimensions, suggesting the influence of anisotropic interactions.