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Characterization of Thermal Transport in One-dimensional Solid Materials
Published on: January 26, 2014
Thermodynamics of soft anisotropic interfaces
1Department of Chemical Engineering, McGill University, 3610 University Street, Montreal, Quebec, H3A 2B2 Canada. alejandro.rey@mcgill.ca
The Journal of Chemical Physics
|July 23, 2004
Summary
This study formulates a generalized Gibbs-Duhem equation for liquid crystal interfaces, revealing couplings between shape, adsorption, and molecular orientation. This leads to a model for adsorption-induced interfacial shape selection, crucial for soft anisotropic materials.
Area of Science:
- Soft Matter Physics
- Materials Science
- Thermodynamics
Background:
- The Gibbs-Duhem equation traditionally describes bulk thermodynamic systems.
- Interfaces between liquid crystals and isotropic fluids exhibit complex behaviors influenced by anisotropy and order.
- Understanding interfacial thermodynamics is key to controlling soft material properties.
Purpose of the Study:
- To formulate a generalized Gibbs-Duhem equation applicable to nematic liquid crystal-isotropic fluid interfaces.
- To establish a connection between nematic and crystalline surface thermodynamics.
- To develop a model for adsorption-induced interfacial shape selection (morphactancy).
Main Methods:
- Formulation of the Gibbs-Duhem equation for soft anisotropic surfaces.
- Establishment of a one-to-one correspondence with crystalline surface equations.
- Analysis using a phase space incorporating thermodynamics, order, and geometry.
- Merging thermodynamic analysis with nematostatics.
Main Results:
- The generalized nematic surface Gibbs-Duhem equation reveals couplings between interfacial shape, adsorption, temperature, and molecular orientation.
- A direct link between nematic and crystalline surface thermodynamics was established.
- Consistency with classical interfacial nematostatics was demonstrated.
- A model for morphactancy was developed.
Conclusions:
- The generalized Gibbs-Duhem equation provides a unified framework for soft anisotropic interfaces.
- The study elucidates the roles of Frank elasticity, interfacial tension, and anchoring energy in morphactancy.
- This work offers insights into adsorption-driven shape changes in liquid crystalline systems.
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