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arXiv · 1612.00641

Linking particle dynamics to local connectivity in colloidal gels

Jan Maarten van Doorn·Jochem Bronkhorst·Ruben Higler·Ties van de Laar·Joris Sprakel
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Abstract

Colloidal gels are a prototypical example of a heterogeneous network solid whose complex properties are governed by thermally-activated dynamics. In this Letter we experimentally establish the connection between the intermittent dynamics of individual particles and their local connectivity. We interpret our experiments with a model that describes single-particle dynamics based on highly cooperative thermal debonding. The model, in quantitative agreement with experiments, provides a microscopic picture for the structural origin of dynamical heterogeneity in colloidal gels and sheds new light on the link between structure and the complex mechanics of these heterogeneous solids.

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Jan Maarten van Doorn, Jochem Bronkhorst, Ruben Higler, Ties van de Laar, Joris Sprakel. 2016-12-02. Linking particle dynamics to local connectivity in colloidal gels. https://doi.org/10.1103/physrevlett.118.188001

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