Calculation of the fractal dimension of aggregates

Simple determination of the fractal dimension as the exponent in the mass-radius relation is possible only when the structure of growing aggregates is scale-invariant. If it is not the case, this method produces artifacts even if the slope in a log-log plot is nearly constant. It is shown that the difference between the fractal dimension and that determined from the slope is significant for diffusion limited particle-cluster aggregates. The fractal dimension of a given aggregate can be determined from its mass and radius of gyration using the proposed fractal dimension dependence of the structural coefficient, the prefactor in mass-radius relation. (C) 2002 Elsevier Science B.V. All rights reserved.