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Published on: August 15, 2018
Range of interlayer interactions in smectic- C liquid crystals.
1Department of Physics, Case Western Reserve University, Cleveland, Ohio 44106-7079, USA.
Summary
Smectic C liquid crystals exhibit an entropy-induced interaction between distant layers, favoring parallel or antiparallel alignment of directors. This interaction
Area of Science:
- Soft Matter Physics
- Liquid Crystal Science
Background:
- Smectic C liquid crystals possess distinct elastic constants for bending along and perpendicular to the c director.
- This anisotropy in bending elasticity has been shown to induce interactions between non-adjacent layers.
Purpose of the Study:
- To theoretically investigate the range and strength of entropy-induced interlayer interactions in smectic C liquid crystals.
- To analyze how these interactions are modified by sample geometry and boundary conditions.
Main Methods:
- Detailed theoretical calculations of interlayer interaction energy.
- Analysis of interaction dependence on material properties (elastic constants, compression modulus) and sample geometry (bulk, confined, free-standing film).
Main Results:
- The interaction's range and strength are primarily determined by the ratio of bending elastic constant to layer compression modulus.
- In bulk samples, the interaction is long-range at low ratios and decays as the inverse cube of distance at high ratios.
- Confined samples show significantly reduced interaction, while free-standing films exhibit complex behavior dependent on surface tension.
Conclusions:
- The anisotropic bending elasticity of smectic C liquid crystals leads to significant interlayer interactions.
- Sample geometry and surface properties critically influence the nature and extent of these interactions.
- Understanding these interactions is crucial for controlling the structure and properties of smectic liquid crystal systems.
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