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Pressure induced tricritical point at the cholesteric-smectic-A phase transition
1Department of Physics, Presidency College, 86/1 College Street, Kolkata 700 073, India. pkmukherje@yahoo.co.in
The Journal of Chemical Physics
|January 7, 2009
Summary
This study presents a theory on how pressure affects the cholesteric to smectic-A phase transition. It reveals a pressure-induced tricritical point where the transition shifts from first to second order.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Thermodynamics
Background:
- The cholesteric to smectic-A phase transition is a key phenomenon in liquid crystal physics.
- Understanding the order of phase transitions (first or second order) is crucial for materials applications.
- The influence of external parameters like pressure on these transitions requires theoretical investigation.
Purpose of the Study:
- To develop a phenomenological theory describing the pressure effect on the cholesteric to smectic-A phase transition.
- To investigate the conditions under which this transition changes its order (first to second order).
- To explore the existence and implications of a tricritical point in the pressure-temperature phase diagram.
Main Methods:
- Development of a phenomenological theory.
- Analysis of the pressure-temperature phase diagram.
- Mathematical exploration of phase transition characteristics.
Main Results:
- A theoretical framework is established to model pressure effects on the cholesteric to smectic-A transition.
- The study demonstrates that pressure can induce a tricritical point.
- At this tricritical point, the first-order transition becomes second-order.
Conclusions:
- The phenomenological theory provides insights into pressure-driven phase transition modifications.
- The existence of a pressure-induced tricritical point is theoretically supported.
- The predicted phase diagram topologies align with experimental observations, validating the theory.
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