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Updated: May 10, 2026
06:26
Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
From permeation to pore nucleation in smectic stacks.
Jean-Luc Buraud1, Olivier Noël, Dominique Ausserré
1Molecular Landscapes, Biophotonic Horizons Group, CNRS-UMR 6087, Université du Maine, Le Mans, Sarthe 72000, France.
Langmuir : the ACS Journal of Surfaces and Colloids
|June 18, 2013
Summary
Researchers observed pore formation during the final stage of liquid crystal droplet spreading on a hydrophilic surface. This pore nucleation is driven by chemical potential differences between layers, not lateral tension.
Area of Science:
- Materials Science
- Soft Matter Physics
- Surface Science
Background:
- The spreading of stratified droplets involves complex layer evolution, particularly in the transition from multilayer to monolayer structures.
- Understanding the final stages of droplet spreading is crucial for controlling thin film formation and surface properties.
- Smectic liquid crystals exhibit unique stratified structures that influence their wetting behavior.
Purpose of the Study:
- To investigate the phenomenon of bilayer vanishing during the spreading of 8CB smectic liquid crystal on a hydrophilic surface.
- To analyze the mechanism of pore formation within the receding bilayer.
- To elucidate the driving forces behind pore nucleation in this specific wetting scenario.
Main Methods:
- Real-time experimental observations of the smectic liquid crystal droplet spreading process.
- Analysis of pore and dislocation structures within the receding bilayer.
- Application of a theoretical approach for smectic liquid nanodrop spreading.
Main Results:
- Pore formation was observed in the outer part of the receding bilayer during the trilayer to monolayer transition.
- Dislocation loops bordering these pores were found at different heights within the trilayer stack compared to dislocation lines bordering the bilayer.
- Experimental results suggest pore nucleation is triggered by chemical potential differences between adjacent liquid crystal layers.
Conclusions:
- The study challenges the classical explanation of pore nucleation being solely due to lateral tension.
- Chemical potential gradients between adjacent layers are identified as the primary driver for pore nucleation in this system.
- The findings provide new insights into the nanoscale dynamics of stratified droplet spreading and thin film evolution.
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