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Updated: Jun 22, 2026
06:26
Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Reversibly tunable helicity induction and inversion in liquid crystal self-assembly by a planar chiroptic trigger
Manoj Mathews1, Nobuyuki Tamaoki
1Liquid Crystal Institute, Kent State University, Kent, OH 44242, USA.
Chemical Communications (Cambridge, England)
|June 13, 2009
Summary
Researchers reversibly controlled helical pitch and handedness in liquid crystals using light and heat. This was achieved by isomerizing a chiral azobenzenophane molecule, offering new possibilities for advanced materials.
Area of Science:
- Materials Science
- Photochemistry
- Liquid Crystal Physics
Background:
- Cholesteric liquid crystals exhibit helical structures that influence their optical properties.
- Controlling these helical structures is crucial for developing advanced optical and electronic devices.
- Existing methods for controlling liquid crystal phases often lack reversibility or precise tunability.
Purpose of the Study:
- To achieve reversible control over helical pitch length in induced cholesteric liquid crystals.
- To invert the helical handedness of the cholesteric phase using external stimuli.
- To explore the potential of planar chiral azobenzenophane molecules in liquid crystal applications.
Main Methods:
- Utilizing photochemical isomerization of a planar chiral azobenzenophane molecule.
- Employing thermal isomerization as a complementary method for molecular switching.
- Inducing a cholesteric liquid crystal phase and monitoring changes in helical structure.
Main Results:
- Demonstrated reversible tuning of the helical pitch length in the cholesteric phase.
- Successfully inverted the helical handedness of the liquid crystal phase.
- Established a direct correlation between molecular isomerization and macroscopic helical structure changes.
Conclusions:
- Planar chiral azobenzenophane molecules offer a viable route for dynamic control of cholesteric liquid crystal properties.
- The combined photochemical and thermal isomerization approach provides a versatile tool for manipulating helical structures.
- This work opens avenues for novel applications in responsive materials and photonic devices.
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