Controlling crystallization: What liquid structure and dynamics reveal about crystal nucleation mechanisms

TL;DR

This paper reviews how molecular simulations reveal the role of liquid structure and dynamics, especially heterogeneity, in crystal nucleation and polymorph selection, offering insights for controlling crystallization.

Contribution

It highlights recent advances in understanding the link between liquid heterogeneity and crystallization, emphasizing the influence of templates and structural dynamics.

Findings

Liquid heterogeneity influences nucleation probability.

Structural and dynamical properties of precursors affect polymorph formation.

Templates modify liquid properties, impacting crystallization pathways.

Abstract

Over recent years, molecular simulations have provided invaluable insights into the microscopic processes governing the initial stages of crystal nucleation and growth. A key aspect that has been observed in many different systems is the formation of precursors in the supercooled liquid that precedes the emergence of crystalline nuclei. The structural and dynamical properties of these precursors determine to a large extend the nucleation probability as well as the formation of specific polymorphs. This novel microscopic view on nucleation mechanisms has further implications for our understanding of the nucleating ability and polymorph selectivity of nucleating agents, as these appear to be strongly linked to their ability in modifying structural and dynamical characteristics of the supercooled liquid, namely liquid heterogeneity. In this perspective, we highlight recent progress in exploring the connection between liquid heterogeneity and crystallization, including the effects of templates, and the potential impact for controlling crystallization processes.