On the influence of a patterned substrate on crystallization in suspensions of hard spheres

TL;DR

This study uses computer simulations to explore how patterned substrates influence crystallization in hard sphere suspensions, revealing substrate-dependent nucleation behaviors and the absence of amorphous precursors in heterogeneous nucleation.

Contribution

It demonstrates the effects of different substrate strains on crystallization pathways and nucleation types in hard sphere suspensions, providing new insights into substrate-induced crystallization.

Findings

Compressed substrates promote immediate crystallization without induction time.

Stretched substrates lead to heterogeneous nucleation with fluctuating crystallite shapes.

No amorphous precursors are observed in heterogeneous nucleation cases.

Abstract

We present a computer simulation study on crystal nucleation and growth in supersaturated suspensions of mono-disperse hard spheres induced by a triangular lattice substrate. The main result is that compressed substrates are wet by the crystalline phase (the crystalline phase directly appears without any induction time), while for stretched substrates we observe heterogeneous nucleation. The shapes of the nucleated crystallites fluctuate strongly. In the case of homogeneous nucleation amorphous precursors have been observed (Phys. Rev. Lett. {\bf 105}(2):025701 (2010)). For heterogeneous nucleation we do not find such precursors. The fluid is directly transformed into highly ordered crystallites.