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Structural Transition Models for a class of Irreversible Aggregates

E. Canessa
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Abstract

A progress report on two recent theoretical approaches proposed to understand the physics of irreversible fractal aggregates showing up a structural transition from a rather dense to a more multibranched growth is presented. In the first approach the transition is understood by solving the Poisson equation on a squared lattice. The second approach is based on the discretization of the Biharmonic equation. Within these models the transition appears when the growth velocity at the fractal surface presents a minimum. The effects of the surrounding medium and geometrical constraints for the seed particles are considered. By using the optical diffraction method, the structural transition is further characterized by a decrease in the fractal dimension for this peculiar class of aggregates.

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E. Canessa. 1995-03-02. Structural Transition Models for a class of Irreversible Aggregates. https://arxiv.org/abs/cond-mat/9503015

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