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arXiv · 0903.2929

Colloidal systems with competing interactions: from an arrested repulsive cluster phase to a gel

Juan Carlos Fernandez Toledano·Francesco Sciortino·Emanuela Zaccarelli
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Abstract

We report an extensive numerical study of a charged colloidal system with competing short-range depletion attraction and long-range electrostatic repulsion. By analizing the cluster properties, we identify two distinct regions in the phase diagram: a state composed of stable finite-size clusters, whose relative interactions are dominated by long-range repulsion, and a percolating network. Both states are found to dynamically arrest at low temperatures, providing evidence of the existence of two distinct non-ergodic states in these systems: a Wigner glass of clusters and a gel.

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Juan Carlos Fernandez Toledano, Francesco Sciortino, Emanuela Zaccarelli. 2009-03-17. Colloidal systems with competing interactions: from an arrested repulsive cluster phase to a gel. https://doi.org/10.1039/b818169a

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