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Updated: Aug 11, 2026
10:37
Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
Attraction-limited cluster-cluster aggregation of Ising dipolar particles
Naoki Yoshioka1, Imre Varga, Ferenc Kun
1Department of Applied Physics, School of Engineering, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan. yoshioka@acolyte.t.u-tokyo.ac.jp
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|February 21, 2006
Summary
This study examines cluster aggregation in 2D Ising dipolar systems. We found that particle size diversity impacts aggregation dynamics above a critical concentration, influenced by cluster screening effects.
Area of Science:
- Condensed Matter Physics
- Statistical Mechanics
Background:
- Investigates cluster-cluster aggregation phenomena in magnetic systems.
- Focuses on two-dimensional Ising dipolar particles, considering particle-size dispersity.
Purpose of the Study:
- To analyze the attraction-limited cluster-cluster aggregation dynamics.
- To determine the influence of particle-size dispersity on aggregation.
- To explore the role of screening effects in dilute systems.
Main Methods:
- Simulation of two-dimensional Ising dipolar particle aggregation.
- Analysis of cluster size distribution and dynamics.
- Application of dynamic scaling theory (Vicsek and Family).
Main Results:
- Observed a rapid decrease in the number of even-sized, smaller clusters.
- Identified a threshold concentration influencing aggregation dynamics.
- Demonstrated that dynamics above the threshold depend on particle-size dispersity.
- Suggested screening effects impact dynamic exponents even in dilute limits.
Conclusions:
- Aggregation dynamics are concentration-dependent and influenced by particle-size dispersity.
- Screening effects play a significant role in the aggregation process, even at low concentrations.
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