Diffusivity and configurational entropy maxima in short range attractive colloids

TL;DR

This study investigates the relationship between diffusivity and configurational entropy in short-range attractive colloids, revealing a maximum in both properties at similar temperatures, indicating a link between dynamics and configurational states.

Contribution

It demonstrates the correlation between diffusivity maxima and configurational entropy peaks in short-range colloidal systems using two different entropy calculation methods.

Findings

Diffusivity exhibits a maximum as a function of temperature.

Configurational entropy also shows a maximum near the diffusivity peak.

The results suggest a connection between particle dynamics and the number of accessible states.

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.