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Updated: May 28, 2026
12:29
Optimization of Crystal Growth for Neutron Macromolecular Crystallography
Published on: March 13, 2021
Minimum free-energy pathway of nucleation
1GPM, UMR CNRS 6634 BP 12, Université de Rouen, Avenue de l'Université 76801 Saint Etienne de Rouvray, France. thomas.philippe@etu.univ-rouen.fr
The Journal of Chemical Physics
|October 14, 2011
Summary
Nuclei in two-component systems first enrich to equilibrium, then grow, a universal two-step process. Diffuse interfaces form, with widths saturating at critical nuclei size.
Area of Science:
- Physical Chemistry
- Materials Science
- Thermodynamics
Background:
- Understanding nucleation is crucial for phase transitions in materials.
- The Cahn-Hilliard theory describes continuum nucleation dynamics.
- Characterizing the free-energy landscape is key to studying nucleation pathways.
Purpose of the Study:
- To investigate the nucleation process in a two-component incompressible system.
- To analyze the topology of the free-energy landscape during nucleation.
- To derive properties of a single nucleus from its minimum free-energy pathway (MFEP).
Main Methods:
- Examining the free-energy landscape topology.
- Applying the Cahn-Hilliard continuum theory of nucleation.
- Computing minimum free-energy pathways (MFEPs) using the string method.
Main Results:
- A universal two-step nucleation behavior was identified: enrichment followed by growth.
- Nuclei sharply enrich to equilibrium before initiating growth.
- Embryos exhibit diffuse interfaces along the MFEP, with interface widths saturating at the critical nucleus size.
Conclusions:
- The study reveals a fundamental two-step mechanism governing nucleation in two-component systems.
- Diffuse interfaces and their width dynamics are key characteristics of the nucleation process.
- Findings provide insights into the physics of nucleation and material self-assembly.
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