2022 Annual Meeting

Crystal Growth, Interrupted: Studying Solid–Solid Phase Transformations with Self-Assembly Simulations

Solid–solid phase transformations, or transitions between different crystalline structures of the same solid material, are yet to be fully understood despite their prevalence in nature, with wide implications in areas such as colloidal matter and ceramics. While observing such transitions experimentally proves challenging, computational modeling allows fine-tuning of parameters that control crystal growth and access a wide range of structural complexity. By simulating particles that interact via isotropic, multi-well pair potentials using HOOMD-blue, a molecular dynamics particle simulation toolkit, we investigate how solid–solid phase transformations proceed between a variety of self-assembled crystal structures. We induce these transitions by interrupting the crystallization process and changing the interaction potential mid-simulation, effectively “restarting" the simulation from a specified frame. We report different kinds of behavior, depending on which final structure was observed: the initial structure, the structure corresponding to the restarted potential, or a third, unrelated structure. This study provides an improved overall understanding of the mechanisms that drive solid–solid phase transformations and investigates the self-assembly of tunable or switchable materials for future applications.