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Updated: May 20, 2026
08:01
A Microfluidic Approach for the Study of Ice and Clathrate Hydrate Crystallization
Published on: August 18, 2022
The microscopic pathway to crystallization in supercooled liquids.
1Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan.
Scientific Reports
|July 14, 2012
Summary
Thermal fluctuations drive crystallization via bond orientational order, not density changes. These fluctuations also dictate crystal type and can hinder crystal formation by promoting fivefold structures.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Computational Chemistry
Background:
- Crystallization is crucial for materials science and technology.
- Microscopic understanding of crystallization remains incomplete.
- The role of thermal fluctuations in driving liquid-to-crystal transitions is debated.
Purpose of the Study:
- To elucidate the microscopic mechanism of crystallization.
- To investigate the role of thermal fluctuations in the supercooled liquid to crystal transition.
- To challenge the prevailing theory of density fluctuations initiating nucleation.
Main Methods:
- Computer simulations using the hard-sphere model.
- Analysis of thermal fluctuations, specifically bond orientational order.
- Investigating the influence of density on nucleation pathways.
Main Results:
- Thermal fluctuations in bond orientational order, not density fluctuations, trigger crystallization nucleation.
- Bond orientational fluctuations determine the specific crystal polymorph formed.
- High densities promote fivefold structures, which can impede crystal formation.
Conclusions:
- Reveals a novel mechanism for crystallization driven by bond orientational order fluctuations.
- Highlights the dual role of bond orientational fluctuations in nucleation and polymorph selection.
- Provides new insights into the interplay between crystallization, vitrification, and structural frustration.
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