Related Experiment Video
Updated: Jul 16, 2026
06:26
Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Orientational multiplicity and transitions in liquid crystalline droplets
Rajesh K Goyal1, Morton M Denn
1Benjamin Levich Institute for Physico-Chemical Hydrodynamics and Department of Chemical Engineering, City College of New York, CUNY, New York, New York 10031, USA.
Summary
Liquid crystal droplet orientation states are computed using simulated annealing. Elongated shapes favor surface-induced transitions, revealing energy barriers between stable configurations.
Area of Science:
- Physics
- Materials Science
- Chemistry
Background:
- Liquid crystals exhibit complex orientational behavior influenced by surface interactions.
- Understanding these orientations is crucial for applications in displays and sensors.
- Homeotropic anchoring in liquid crystal droplets presents unique challenges in predicting stable states.
Purpose of the Study:
- To compute orientation distributions in homeotropically anchored liquid crystal droplets.
- To investigate the role of surface-to-elastic forces on droplet orientational states.
- To determine the energy barriers separating different steady-state orientations.
Main Methods:
- Utilized a simulated annealing algorithm to minimize free energy.
- Employed the Oseen-Frank continuum theory for theoretical framework.
- Analyzed droplets with varying spherical and spheroidal shapes.
Main Results:
- Identified multiple orientational steady states in liquid crystal droplets.
- Quantified finite energy barriers separating these states across all force ratios.
- Observed maximum transition energy densities around 2000 J/m3 for spherical droplets.
- Found that transition energy densities decrease with droplet elongation (aspect ratio ≥ 4).
Conclusions:
- Droplet elongation is a favorable mechanism for inducing surface-driven orientational transitions.
- Finite energy barriers suggest bistability or multistability in droplet orientations.
- The findings provide insights into controlling liquid crystal droplet behavior for technological applications.
Related Concept Videos
01:27Two Components: Liquid–Liquid Systems
A pressure-composition phase diagram explicitly describes the behavior of an ideal solution of two volatile liquids under varying pressures and compositions. A pressure-composition diagram has two main curves. The bubble point curve represents the plot of pressure versus liquid mole fraction. It indicates the pressure at which the first bubble of vapor forms from the liquid phase as the system pressure decreases.The dew point curve is the pressure versus vapor mole fraction. It indicates the...
02:39Phase Transitions: Vaporization and Condensation
The physical form of a substance changes on changing its temperature. For example, raising the temperature of a liquid causes the liquid to vaporize (convert into vapor). The process is called vaporization—a surface phenomenon. Vaporization occurs when the thermal motion of the molecules overcome the intermolecular forces, and the molecules (at the surface) escape into the gaseous state. When a liquid vaporizes in a closed container, gas molecules cannot escape. As these gas phase molecules...
01:29Nonideal Two-Component Liquid Solutions
Nonideal liquid solutions, also known as real solutions, do not strictly follow Raoult's law. Raoult's law is a rule of thumb in physical chemistry. However, not all mixtures adhere to this law due to varying molecular interactions. For example, in an acetone/chloroform solution, the individual vapor pressures of the components are lower than expected, resulting in a total vapor pressure below that predicted by Raoult's law, causing a negative deviation.On the other hand, in an ethanol/water...
01:34Fluid Mosaic Model
The fluid mosaic model was first proposed as a visual representation of research observations. The model comprises the composition and dynamics of membranes and serves as a foundation for future membrane-related studies. The model depicts the structure of the plasma membrane with a variety of components, which include phospholipids, proteins, and carbohydrates. These integral molecules are loosely bound, defining the cell’s border and providing fluidity for optimal function.LipidsThe most...
01:19Fluid Mosaic Model
Scientists identified the plasma membrane in the 1890s and its principal chemical components (lipids and proteins) by 1915. The model for plasma membrane structure, proposed in 1935 by Hugh Davson and James Danielli, was the first model to be widely accepted in the scientific community. The model was based on the plasma membrane's "railroad track" appearance in early electron micrographs. Davson and Danielli theorized that the plasma membrane's structure resembled a sandwich with the analogy of...
01:21Polymer Classification: Crystallinity
Unlike ionic or small covalent molecules, polymers do not form crystalline solids due to the diffusion limitations of their long-chain structures. However, polymers contain microscopic crystalline domains separated by amorphous domains.
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...