Flory-type approximation for the fractal dimension of cluster-cluster aggregates

Abstract
We consider the structure and fractal dimension of aggregates formed by cluster-cluster diffusional encounters. Both the fractal dimensions and symmetry properties of these aggregates are found to differ significantly from those found in the case of a single aggregating cluster. We find for the fractal dimension D(d)=d(4d+3)(9d2) for d<dc=8 and D(d)=d2 for d>dc.