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Updated: Jul 3, 2026
06:26
Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Observation of a pretransitional effect near a virtual smectic-A--smectic-C* transition
S Shibahara1, Y Takanishi, J Yamamoto
1Department of Organic and Polymeric Materials, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8552, Japan.
Summary
Unusual softening of the layer compression modulus was observed in a liquid crystal mixture. This phenomenon is linked to pretransitional effects near a vanishing phase transition, similar to supercritical behavior.
Area of Science:
- Materials Science
- Condensed Matter Physics
Background:
- Smectic-C* phase transitions in liquid crystals are crucial for display technologies.
- Understanding phase behavior near vanishing transitions is key to material design.
Purpose of the Study:
- Investigate the unusual softening of the layer compression modulus (B) in a naphthalene-based liquid crystal mixture.
- Determine the cause of this softening near the smectic-C* phase boundary.
Main Methods:
- Systematic X-ray measurements.
- Layer compression modulus measurements.
Main Results:
- Observed unusual softening of the layer compression modulus (B) near the phase boundary where the smectic-C* phase vanishes.
- Attributed the softening to pretransitional effects in the smectic-A phase.
Conclusions:
- The observed phenomenon is related to a virtual smectic-A-smectic-C* phase transition.
- This pretransitional softening in the smectic-A phase is analogous to supercritical behavior but distinct.
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