Dispersive kinetics in discotic liquid crystals.

Area of Science:

• Materials Science
• Condensed Matter Physics
• Physical Chemistry

Background:

• Discotic liquid crystals, such as hexakis (n-hexyloxy) triphenylene (HAT6), exhibit complex dynamics.
• Understanding these dynamics is crucial for applications in advanced materials.
• Previous studies often simplified the dynamic processes involved.

Purpose of the Study:

• To investigate the molecular dynamics of HAT6 in its columnar phase.
• To apply a phenomenological model for rate processes, incorporating long-time scale correlations.
• To link dynamic parameters to nonextensive thermodynamics and fractional diffusion.

Main Methods:

• Utilized experimental quasielastic neutron scattering (QENS) data for HAT6.
• Employed a phenomenological model for rate processes (Berlin model).
• Interpreted model parameters using nonextensive thermodynamics.

Main Results:

• The study reveals that rare local events govern the slower dynamics of the molecular assembly.
• A fractional diffusion equation accurately describes the system's evolution.
• Analysis of waiting-time dependence identified a Lévy distribution of jump lengths.

Conclusions:

• The dynamics of discotic liquid crystals can be effectively described by incorporating rare local events and long-time correlations.
• Nonextensive thermodynamics provides a framework for understanding these complex dynamics.
• The van Hove correlation function was successfully constructed for the HAT6 system.