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Updated: May 1, 2026

Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
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.
Abstract:
We propose a simple theoretical model which explains the formation of dipolar two- (2D) and three-dimensional (3D) colloidal structures in nematic liquid crystals. The colloidal particles are treated as effective hard spheres interacting via their elastic dipole, quadrupole, and octopole moments. It is shown that the octopole moment plays an important role in the formation of 2D and 3D nematic colloidal crystals. We generalize this assumption to the case of an external electric field and theoretically explain a giant electrostriction effect in 3D crystals observed recently.
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