Techniques for the visualization of topological defect behavior in nematic liquid crystals

Area of Science:

• Condensed Matter Physics
• Computational Science
• Data Visualization

Background:

• Molecular simulations generate massive datasets (terabytes) detailing molecular positions and orientations over time.
• Understanding the evolution of topological defects in liquid crystal (LC) systems is crucial for condensed matter physics.

Purpose of the Study:

• To present novel visualization tools for analyzing large-scale molecular simulation data of liquid crystals.
• To facilitate the study of topological defect evolution in LC systems.

Main Methods:

• Converted discrete simulation data into a continuous second-order tensor field.
• Employed AVS software to integrate visualization techniques: colored cutting planes, isosurfaces, and integral curves.
• Displayed tensor field contractions, including Westin's scalar metrics (cl, cp, cs) and principal eigenvectors.

Main Results:

• The visualization tools provide a spatially and temporally smoother representation of the data compared to previous methods.
• Successfully avoided grid effects, enabling clearer observation of molecular behavior and defect dynamics.
• Extended the application of diffusion tensor visualization tools to molecular simulations.

Conclusions:

• The developed tools offer an interactive environment for exploring complex tensor data in LC simulations.
• Addressed long-standing questions concerning molecular orientation around defects and defect conformational changes.
• The system has been actively used in a physics lab for over a year, validating its effectiveness.