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Structure of twist-grain-boundary-C phases
Arindam Kundagrami1, T C Lubensky
1Department of Physics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|February 3, 2004
Summary
Researchers investigated the twist-grain-boundary-C (TGB(C)) phases, finding a generalized model free energy that stabilizes both Renn-Lubensky and Bordeaux TGB(C) phases. Calculations determined critical twist values and order-parameter profiles for these liquid crystal phases.
Area of Science:
- Liquid crystal physics
- Soft matter science
- Materials science
Background:
- The twist-grain-boundary-C (TGB(C)) phase is a complex liquid crystal phase.
- Understanding transitions between TGB(C) and cholesteric phases is crucial for materials applications.
Purpose of the Study:
- To study the properties of Renn-Lubensky TGB(C) and Bordeaux TGB(C) phases.
- To develop a generalized model free energy applicable to both TGB(C) phases.
- To calculate the critical twist and order-parameter profiles for these phases.
Main Methods:
- Development of a generalized model free energy for the smectic-C phase.
- Theoretical calculation of the upper critical twist (k(c2)).
- Analysis of the order-parameter profile within the TGB(C) phases.
Main Results:
- The generalized model successfully allows for the stability of both Renn-Lubensky and Bordeaux TGB(C) phases.
- Calculated values for k(c2) were obtained for both phases.
- The order-parameter profile exhibits only modest spatial variation.
Conclusions:
- A unified theoretical framework can describe different TGB(C) phases.
- The transition to the cholesteric phase is characterized by a specific critical twist value.
- The spatial variation of the order parameter is limited in these TGB(C) phases.