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Small Angle Scattering by Fractal Aggregates: A Numerical Investigation of the Crossover Between the Fractal Regime and the Porod Regime

Anwar Hasmy·René Vacher·Rémi Jullien
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Abstract

Fractal aggregates are built on a computer using off-lattice cluster-cluster aggregation models. The aggregates are made of spherical particles of different sizes distributed according to a Gaussian-like distribution characterised by a mean $a_0$ and a standard deviation $σ$. The wave vector dependent scattered intensity $I(q)$ is computed in order to study the influence of the particle polydispersity on the crossover between the fractal regime and the Porod regime. It is shown that, given $a_0$, the location $q_c$ of the crossover decreases as $σ$ increases. The dependence of $q_c$ on $σ$ can be understood from the evolution of the shape of the center-to-center interparticle-distance distribution function.

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Anwar Hasmy, René Vacher, Rémi Jullien. 1995-04-12. Small Angle Scattering by Fractal Aggregates: A Numerical Investigation of the Crossover Between the Fractal Regime and the Porod Regime. https://doi.org/10.1103/physrevb.50.1305

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