Cholesteric ordering predicted using a coarse-grained polymeric model with helical interactions
1School of Chemistry and Chemical Engineering, Key Laboratory of Scientific and Engineering Computing of Ministry of Education, Shanghai Jiao Tong University, 200240, Shanghai, China. huaisun@sjtu.edu.cn.
Soft Matter
|December 7, 2017
Summary
A new coarse-grained model simulates cholesteric liquid crystals, revealing chain flexibility
Area of Science:
- Materials Science
- Computational Chemistry
- Soft Matter Physics
Background:
- Understanding cholesteric liquid crystals at the molecular level is difficult.
- Bridging molecular structures and macroscopic chiral organization requires further insight.
Purpose of the Study:
- To introduce a novel coarse-grained (CG) molecular model for simulating cholesteric liquid crystals.
- To investigate the relationship between molecular characteristics and macroscopic phase behavior.
Main Methods:
- Utilized molecular dynamics (MD) simulations with a flexible chain particle model (FCh).
- Simulated isotropic-cholesteric phase transitions and employed wall confinement to determine cholesteric pitch.
Main Results:
- Observed left-handed cholesteric phases for right-handed chiral interactions.
- Found that chain flexibility significantly influences cholesteric pitch and phase structure.
- Detected spatially inhomogeneous nematic order parameter profiles.
Conclusions:
- The FCh model provides insights into cholesteric liquid crystal behavior.
- Chain flexibility is a key factor in determining macroscopic properties.
- Established a link between microscopic molecular features and macroscopic phase behavior.
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