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Scaling of dynamics with the range of interaction in short-range attractive colloids

G. Foffi·C. De Michele·F. Sciortino·P. Tartaglia
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Abstract

We numerically study the dependence of the dynamics on the range of interaction $Δ$ for the short-range square well potential. We find that, for small $Δ$, dynamics scale exactly in the same way as thermodynamics, both for Newtonian and Brownian microscopic dynamics. For interaction ranges from a few percent down to the Baxter limit, the relative location of the attractive glass line and the liquid-gas line does not depend on $Δ$. This proves that in this class of potentials, disordered arrested states (gels) can be generated only as a result of a kinetically arrested phase separation.

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G. Foffi, C. De Michele, F. Sciortino, P. Tartaglia. 2004-10-14. Scaling of dynamics with the range of interaction in short-range attractive colloids. https://doi.org/10.1103/physrevlett.94.078301

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