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Updated: Aug 16, 2026
11:54
Ligand-Mediated Nucleation and Growth of Palladium Metal Nanoparticles
Published on: June 25, 2018
Recent developments in the kinetic theory of nucleation
1Department of Chemical and Biological Engineering, SUNY at Buffalo, Buffalo, NY 14260, USA. feaeliru@acsu.buffalo.edu
Advances in Colloid and Interface Science
|September 3, 2005
Summary
A new nucleation theory based on molecular interactions offers a more accurate prediction of nucleation rates, especially for small clusters, by avoiding macroscopic surface tension assumptions. This approach provides insights into both liquid-to-solid and vapor-to-liquid phase transitions.
Area of Science:
- Physical Chemistry
- Materials Science
- Chemical Physics
Background:
- Conventional kinetic theory of nucleation relies on thermodynamics and the free energy of formation for new-phase particles.
- This approach necessitates knowledge of surface tension for tiny clusters, a concept with inherent complexities and controversies.
- Existing methods like capillarity approximation, density functional theory, and molecular simulation have limitations.
Purpose of the Study:
- To present a novel kinetic theory of nucleation based on molecular interactions, bypassing traditional thermodynamic assumptions.
- To develop a framework applicable to both liquid-to-solid and vapor-to-liquid phase transitions.
- To provide a more accurate prediction of nucleation rates, particularly for small critical clusters.
Main Methods:
- Utilized mean first passage time analysis to determine the rate of molecule emission by new-phase particles.
- Solved single-molecule master equations (Fokker-Planck, Smoluchowski) describing molecular behavior within a cluster's potential field.
- Employed molecular pair interaction potentials (dispersive attraction and hard-sphere repulsion) for numerical illustrations.
Main Results:
- The new theory yields an equation for critical radius that converges to the Kelvin equation for large clusters.
- Nucleation rates are shown to be dependent on cluster structure (amorphous, fcc, icosahedral) in liquid-to-solid transitions.
- For small critical clusters, the new theory predicts higher nucleation rates compared to classical nucleation theory (CNT).
Conclusions:
- The proposed molecular interaction-based theory offers a more accurate description of nucleation kinetics than traditional thermodynamic approaches.
- It resolves the issue of surface tension for small clusters, providing better predictions for nucleation rates.
- The theory's consistency with CNT for large clusters and improved accuracy for small clusters highlight its potential.
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