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Published on: March 24, 2018
Interlayer interactions in enantiomeric anticlinic liquid crystalline mixtures
1Department of Physics, Case Western Reserve University, Cleveland, Ohio 44106, USA.
Summary
The interlayer interaction coefficient U in anticlinic liquid crystal phases was measured. It increases with lower temperatures and decreases with reduced enantiomer excess in binary mixtures.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Physical Chemistry
Background:
- Anticlinic liquid crystal phases exhibit unique interlayer interactions.
- Enantiomeric binary mixtures offer tunable properties compared to optically pure materials.
Purpose of the Study:
- To determine the interlayer interaction coefficient (U) in anticlinic phases of enantiomeric binary mixtures.
- To investigate the influence of temperature and enantiomeric excess (X) on U.
Main Methods:
- Measuring the threshold electric field for solitary wave onset.
- Analyzing the ratio of U in mixtures to U in optically pure materials across varying enantiomeric excess and polar angles.
Main Results:
- The interlayer interaction coefficient (U) increases as temperature decreases within the anticlinic phase for a fixed enantiomer excess (X).
- The ratio U(X, θ)/U(X=1, θ) is notably smaller for mixtures with low enantiomer excess compared to optically pure materials.
- Observed behaviors were analyzed using a mean-field model focusing on dipole-dipole interactions between adjacent layers.
Conclusions:
- Temperature and enantiomeric composition significantly affect interlayer interactions in anticlinic liquid crystal phases.
- The findings provide insights into the physical mechanisms governing the behavior of chiral liquid crystal mixtures.
- The mean-field model successfully explains the observed trends in interlayer interactions.
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