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Updated: Mar 31, 2026
11:54
Ligand-Mediated Nucleation and Growth of Palladium Metal Nanoparticles
Published on: June 25, 2018
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Dynamics of homogeneous nucleation.
1DNRF Centre "Glass and Time," IMFUFA, Department of Sciences, Roskilde University, P.O. Box 260, DK-4000 Roskilde, Denmark.
The Journal of Chemical Physics
|October 24, 2015
Summary
Classical nucleation theory is challenged by molecular dynamics simulations, revealing that small, cold clusters initiate nucleation. These clusters maintain a lower temperature until reaching critical size, influencing nucleation kinetics beyond simple monomer addition.
Area of Science:
- Physical Chemistry
- Thermodynamics
- Materials Science
Background:
- Classical nucleation theory describes homogeneous nucleation as a density fluctuation in supersaturated gases.
- This theory assumes nucleation is driven by monomer accretion/evaporation and uniform gas temperature.
Purpose of the Study:
- To investigate the initial stages of homogeneous nucleation using molecular dynamics simulations.
- To compare simulation findings with classical nucleation theory predictions regarding cluster temperature and kinetics.
Main Methods:
- Molecular dynamics simulations of supersaturated gas systems.
- Analysis of cluster formation, temperature fluctuations, and size dynamics during nucleation.
Main Results:
- Nucleation is initiated by small, cold clusters, not density fluctuations.
- Nucleating clusters exhibit sub-gas temperatures until critical size is reached.
- Nucleation kinetics are influenced by cluster size distribution and temperature-dependent growth/shrinkage rates.
Conclusions:
- Molecular dynamics simulations provide a more detailed view of homogeneous nucleation.
- Classical nucleation theory requires refinement to account for cluster temperature dynamics and complex kinetics.
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