Crystal Nucleation of Colloidal Suspensions under Shear

TL;DR

This study uses simulations to show that shear flow suppresses crystal nucleation in colloidal suspensions and alters nucleus orientation, extending classical nucleation theory to explain these effects.

Contribution

It introduces a phenomenological extension of classical nucleation theory to account for shear effects on nucleation rate, nucleus size, and orientation.

Findings

Shear suppresses nucleation rate

Critical nucleus size increases under shear

Nucleus orientation is tilted with respect to shear direction

Abstract

We use Brownian Dynamics simulations in combination with the umbrella sampling technique to study the effect of shear flow on homogeneous crystal nucleation. We find that a homogeneous shear rate leads to a significant suppression of the crystal nucleation rate and to an increase of the size of the critical nucleus. A simple, phenomenological extension of classical nucleation theory accounts for these observations. The orientation of the crystal nucleus is tilted with respect to the shear direction.