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Published on: May 29, 2018
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Elastic octopoles and colloidal structures in nematic liquid crystals.
S B Chernyshuk1, O M Tovkach2, B I Lev2
1Institute of Physics, NAS Ukraine, Prospekt Nauki 46, Kyiv 03650, Ukraine.
Summary
We present a theoretical model for colloidal crystal formation in liquid crystals. The octopole moment is key to creating 2D and 3D structures, and explains giant electrostriction effects under electric fields.
Area of Science:
- Soft Matter Physics
- Colloidal Science
- Liquid Crystal Physics
Background:
- Nematic liquid crystals exhibit complex phase behaviors.
- Colloidal particles in liquid crystals can self-assemble into ordered structures.
- Understanding particle interactions is crucial for controlling self-assembly.
Purpose of the Study:
- To develop a theoretical model for dipolar colloidal structure formation in nematic liquid crystals.
- To investigate the role of multipole moments in self-assembly.
- To explain the giant electrostriction effect in 3D nematic colloidal crystals.
Main Methods:
- Theoretical modeling of colloidal particles as effective hard spheres.
- Analysis of inter-particle interactions including dipole, quadrupole, and octopole moments.
- Generalization of the model to include external electric fields.
Main Results:
- The octopole moment is identified as a critical factor in the formation of both 2D and 3D nematic colloidal crystals.
- The theoretical model successfully explains the observed giant electrostriction effect in 3D crystals under an external electric field.
- The model provides a framework for understanding and predicting colloidal self-assembly in liquid crystalline environments.
Conclusions:
- The octopole moment significantly influences the self-assembly of colloidal particles in nematic liquid crystals.
- The developed theoretical model offers insights into the mechanisms behind colloidal crystal formation and electrostriction.
- This work contributes to the fundamental understanding of soft matter systems and their response to external stimuli.
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