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Spatially modulated structures in nematic colloids: Statistical thermodynamics and kinetics
A V Kleshchonok1, V Yu Reshetnyak, V A Tatarenko
1Taras Shevchenko National University of Kyiv, Physics Faculty, Ukraine. avklesh@gmail.com
The European Physical Journal. E, Soft Matter
|March 31, 2011
Summary
Colloidal particles in nematic liquid crystals form superstructures due to long-range interactions. This study analyzes the conditions for modulated lamellar structures and provides an analytical expression for structure formation temperature.
Area of Science:
- Physics
- Materials Science
- Soft Matter Physics
Background:
- Nematic liquid crystals exhibit unique properties due to anisotropic molecular ordering.
- Colloidal particles dispersed in liquid crystals can interact via long-range forces.
- Understanding particle interactions is key to controlling emergent structures.
Purpose of the Study:
- To investigate the spatial distribution of rigid-sphere-like particles in a nematic host.
- To analyze the conditions leading to the formation of modulated lamellar structures.
- To derive an analytical expression for the temperature of instability towards modulated structure formation.
Main Methods:
- Utilized a continuum model to analyze particle interactions and structure formation.
- Considered both direct van der Waals interactions and indirect interactions via director field distortions.
- Investigated the influence of temperature, particle-host coupling energy, and particle concentration.
Main Results:
- Identified a long-range effective interaction between colloidal particles.
- Demonstrated that this interaction can lead to the formation of superstructures.
- Derived an analytical expression for the critical temperature at which modulated structures form.
Conclusions:
- The effective interaction, influenced by temperature and particle properties, governs the spatial organization of particles.
- Modulated lamellar structures can emerge from the interplay of direct and indirect particle interactions.
- The findings provide insights into the self-assembly of colloidal systems in liquid crystals.
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