Role of Spatially Heterogeneous Dynamics and Polydispersity in the Early Stages of Homogeneous Nucleation: Application to the Promotion and Suppression of Crystallization and Vitrification |
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Materials:
Nanomaterials
Metals
Semiconductors
Application: Nanotechnology Structural Technique: Computation |
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Supercooled and supersaturated liquids are metastable liquids that typically crystallize after sufficient time has passed. Rapid cooling or densification can suppress homogeneous nucleation of the crystal phase, leading to vitrification and the transformation of the liquid into a glass. Polydispersity in the sizes of the atoms or particles comprising the liquid can also inhibit crystallization. We are carrying out molecular dynamics simulations to study the local structure and dynamics of supercooled atomic and molecular liquids and supersaturated colloidal liquids prior to and during nucleation. In collaboration with the Solomon group, who use confocal microscopy to directly view particle motion in supersaturated colloidal suspensions, we are determining the fundamental issues controlling vitrification vs. homogeneous nucleation in model liquids approaching their glass transition. |