Does Local Structure Bias How a Crystal Nucleus Evolves?
The broad scientific and technological importance of crystallization has led to significant research probing and rationalizing crystallization processes, particularly how nascent
crystal phases appear. Previous work has generally neglected the possibility of the molecular-level dynamics of individual nuclei coupling to local structures (e.g., that of the nucleus and its
surrounding environment). However, recent experimental work has conjectured that this can occur. Therefore, to address a deficiency in scientific understanding of crystallization, we have
probed the nucleation of prototypical single and multi-component crystals (specifically, ice and mixed gas hydrates). Here, we establish that local structures can bias the evolution of nascent
crystal phases on a nanosecond timescale by, for example, promoting the appearance or disappearance of specific crystal motifs, and thus reveal a new facet of crystallization behaviour.
Analysis of the crystallization literature confirms that structural biases are likely present during crystallization processes beyond ice and gas hydrate formation. Moreover, we demonstrate that
structurally-biased dynamics are a lens for understanding existing computational and experimental results while pointing to future opportunities.