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Molecular model for de Vries type smectic- A -smectic- C phase transition in liquid crystals
M V Gorkunov1, F Giesselmann, J P F Lagerwall
1Department of Mathematics, University of Strathclyde, Glasgow G1 1XH, United Kingdom.
Summary
We developed a theory for the smectic A to smectic C phase transition, explaining weak layer contraction in liquid crystals. Our model accurately predicts experimental results for various smectic types.
Area of Science:
- Soft Matter Physics
- Liquid Crystal Science
- Materials Science
Background:
- The smectic A to smectic C phase transition is crucial in liquid crystal displays.
- Anomalously weak smectic layer contraction presents a theoretical challenge.
Purpose of the Study:
- To develop a unified theory for the smectic A-smectic C phase transition.
- To explain the phenomenon of weak smectic layer contraction.
- To provide a model applicable to both conventional and de Vries type smectics.
Main Methods:
- Development of a phenomenological and molecular-statistical theory.
- Utilizing a general mean-field molecular model.
- Analysis of interaction potentials governing the phase transition.
Main Results:
- A simple interaction potential successfully describes the smectic A-smectic C transition.
- The theory accurately reproduces experimental data for weak layer contraction.
- The model is validated for both conventional and de Vries smectics.
Conclusions:
- The developed theory offers a robust explanation for the smectic A-smectic C transition with weak layer contraction.
- The mean-field molecular model provides a versatile framework for soft matter systems.
- This approach can be extended to analyze tilting transitions in other soft materials.
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