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The Impact of Colloidal Surface-Anchoring on the Smectic A Phase
Sergej Püschel-Schlotthauer1, Victor Meiwes Turrión2, Carol K Hall3
1Stranski-Laboratorium für Physikalische und Theoretische Chemie, Fakultät für Mathematik und Naturwissenschaften, Technische Universität Berlin , Straße des 17. Juni 135, 10623 Berlin, Germany.
Langmuir : the ACS Journal of Surfaces and Colloids
|February 7, 2017
Summary
Colloidal particles disrupt liquid crystal order, creating defects like Saturn rings and onion structures in smectic A phases. Understanding these perturbations is key to controlling colloidal self-assembly.
Area of Science:
- Physics
- Materials Science
- Chemistry
Background:
- Liquid crystals exhibit fluidity and ordered structures, crucial for self-assembly.
- Colloidal particles locally perturb these ordered liquid crystal phases.
- Understanding these perturbations is vital for controlling colloidal self-assembly.
Purpose of the Study:
- Investigate order perturbations in smectic A liquid crystals caused by spherical colloids.
- Utilize Monte Carlo simulations to model defect formation and structures.
- Explore the impact of varying anchoring conditions on defect morphology.
Main Methods:
- Monte Carlo simulations were employed to study the system.
- A specific interaction potential was used to model the smectic A phase.
- Simulations analyzed orientational and positional order disruptions around a colloid.
Main Results:
- Strong homeotropic anchoring yielded a Saturn ring defect and a novel onion structure.
- Strong planar anchoring resulted in elongated Boojum defects at lower temperatures.
- Weak planar anchoring conditions led to the formation of a double surface ring defect.
Conclusions:
- Colloid-induced defects in smectic A phases are diverse and depend on anchoring strength.
- The discovery of onion structures offers new insights into colloidal behavior in liquid crystals.
- Simulation results provide a foundation for predicting and manipulating colloidal self-assembly.
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