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arXiv · cond-mat/0404604

Diffusivity and configurational entropy maxima in short range attractive colloids

Luca Angelani·Giuseppe Foffi·Francesco Sciortino·Piero Tartaglia
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Abstract

We study tagged particle diffusion at large packing fractions, for a model of particles interacting with a generalized Lennard-Jones 2n-n potential, with large n. The resulting short-range potential mimics interactions in colloidal systems. In agreement with previous calculations for short-range potential, we observe a diffusivity maximum as a function of temperature. By studying the temperature dependence of the configurational entropy -- which we evaluate with two different methods -- we show that a configurational entropy maximum is observed at a temperature close to that of the diffusivity maximum. Our findings suggest a relationbetween dynamics and number of distinct states for short-range potentials.

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Luca Angelani, Giuseppe Foffi, Francesco Sciortino, Piero Tartaglia. 2004-04-25. Diffusivity and configurational entropy maxima in short range attractive colloids. https://doi.org/10.1088/0953-8984%2F17%2F12%2Fl02

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