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Updated: Jan 19, 2026
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High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
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Electrostatically controlled surface boundary conditions in nematic liquid crystals and colloids
Haridas Mundoor1, Bohdan Senyuk1, Mahmoud Almansouri1
1Department of Physics and Soft Materials Research Center, University of Colorado, Boulder, CO 80309, USA.
Science Advances
|September 27, 2019
Summary
Surface functionalization and electric fields control liquid crystal alignment, enabling tunable orientation of colloidal particles and reconfigurable colloidal crystals with anisotropic properties.
Area of Science:
- Soft Matter Physics
- Materials Science
- Colloid Science
Background:
- Liquid crystals display anisotropic interactions with surfaces, influencing molecular alignment at interfaces.
- Controlling molecular orientation is key for manipulating colloidal behavior in liquid crystal hosts.
Purpose of the Study:
- To demonstrate control over nematic liquid crystal surface alignment using competing surface functionalization and electric field effects.
- To show how ionic content influences particle orientation and director alignment within liquid crystals.
- To enable the creation of reconfigurable colloidal crystals with tunable symmetries.
Main Methods:
- Investigated competing aligning effects of surface functionalization and electric fields.
- Manipulated ionic content in bulk and at surfaces.
- Analyzed anisotropic elastic and electrostatic interactions.
Main Results:
- Achieved controlled surface alignment of nematic molecules.
- Tuned orientations of shape-anisotropic colloidal particles (e.g., platelets).
- Modified director orientation relative to confining substrates.
- Enabled reconfigurable colloidal crystals with adjustable symmetries and inclusion orientations.
Conclusions:
- Surface and bulk ionic control offers a versatile method for manipulating liquid crystal-colloid systems.
- Anisotropic interactions facilitate the design of responsive materials with dynamic properties.
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