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Updated: May 29, 2026
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Optimization of Crystal Growth for Neutron Macromolecular Crystallography
Published on: March 13, 2021
Effect of immobile impurities on two-dimensional nucleation
Hiroyasu Katsuno1, Kiiko Katsuno, Masahide Sato
1Computer Centre, Gakushuin University, 1-5-1 Mejiro, Toshsima-ku, Tokyo 171-8588, Japan.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 21, 2011
Summary
Increasing impurity density on crystal surfaces enlarges the critical nucleus size. At high densities, the critical nucleus size diverges, causing clusters to vanish over time.
Area of Science:
- Surface science
- Computational physics
- Materials science
Background:
- Understanding nucleation processes is crucial for materials fabrication and surface modification.
- Impurity atoms on crystal surfaces can significantly influence nucleation kinetics and stability.
- The critical nucleus size determines the threshold for stable cluster formation.
Purpose of the Study:
- To investigate the impact of impurity density on the critical nucleus size during cluster formation on a crystal surface.
- To determine the relationship between impurity concentration and the stability of adsorbed clusters.
- To explore the conditions under which nucleation may be completely suppressed.
Main Methods:
- Monte Carlo simulation was employed to model cluster dynamics.
- The simulation focused on a system with a single initial cluster.
- The study assumed fixed impurity positions and neglected bond restoration between impurity and adsorbed atoms.
Main Results:
- The critical nucleus size was found to increase with rising impurity density.
- A critical point was identified where the rate of cluster growth equals the rate of decay.
- At sufficiently high impurity densities, the critical nucleus size diverges, leading to cluster disappearance.
Conclusions:
- Impurity density is a key factor controlling critical nucleus size and nucleation probability.
- High impurity concentrations can inhibit stable cluster formation on crystal surfaces.
- The findings have implications for controlling thin-film growth and surface patterning.
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