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Updated: Jun 28, 2025
08:37
Forming, Confining, and Observing Microtubule-Based Active Nematics
Published on: January 13, 2023
2.6K
Particle-based and continuum models for confined nematics in two dimensions
Humberto Híjar1, Apala Majumdar2
1Research Center, La Salle University Mexico, Mexico. humberto.hijar@lasalle.mx.
Soft Matter
|April 17, 2024
Summary
We simulated confined liquid crystals in polygons using particle-based methods. Results align with continuum theory, revealing how polygon size affects defect dynamics and relaxation.
Area of Science:
- Soft Matter Physics
- Computational Materials Science
Background:
- Nematic liquid crystals exhibit unique properties when confined in geometric shapes.
- Understanding their behavior requires bridging particle-based and continuum simulation methods.
Purpose of the Study:
- To simulate and analyze confined nematic liquid crystals within 2D polygons using the N-MPCD algorithm.
- To compare particle-based N-MPCD simulations with continuum Landau-de Gennes theory.
- To investigate the influence of polygon size and nematicity on liquid crystal behavior and defect dynamics.
Main Methods:
- Utilized the particle-based stochastic multi-particle collision dynamics (N-MPCD) algorithm.
- Simulated nematic liquid crystals confined in regular 2D polygons (squares, pentagons, hexagons).
- Employed closure arguments to map N-MPCD parameters to the Landau-de Gennes framework.
Main Results:
- N-MPCD averaged configurations agree with Landau-de Gennes theory for larger polygons.
- Relaxation dynamics in N-MPCD show kinetic traps analogous to Landau-de Gennes saddle points.
- Finite-size effects in N-MPCD slow down and attract nematic defects to polygon vertices.
Conclusions:
- The study provides a comprehensive comparison between particle-based (N-MPCD) and continuum (Landau-de Gennes) methods for confined nematics.
- N-MPCD simulations validate continuum theory predictions and offer insights into nanoscale phenomena.
- Findings are crucial for developing advanced multiscale theories in soft matter physics.
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