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06:26
Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Prediction of a structural transition in the hard disk fluid
Jarosław Piasecki1, Piotr Szymczak, John J Kozak
1Institute of Theoretical Physics, University of Warsaw, Hoza 69, 00-681 Warsaw, Poland. jaroslaw.piasecki@fuw.edu.pl
The Journal of Chemical Physics
|November 2, 2010
Summary
Researchers studied correlation decay in dense hard disk and sphere fluids. They found oscillations persist up to a packing fraction of ~0.718 in disks and become impossible in spheres above λ=34.81.
Area of Science:
- Statistical mechanics
- Condensed matter physics
- Computational physics
Background:
- The BBGKY hierarchy describes many-body systems.
- Kirkwood superposition closure is a common approximation.
- Understanding correlation decay is crucial for fluid phase behavior.
Purpose of the Study:
- To investigate the asymptotic decay of correlations in hard disk and hard sphere fluids.
- To determine the conditions under which exponentially damped oscillations occur.
- To explore phase transitions in these systems.
Main Methods:
- Utilizing a new analytical method based on the BBGKY hierarchy with Kirkwood superposition closure.
- Performing complementary numerical studies.
- Analyzing the conditions for exponential damping of oscillations.
Main Results:
- Exponentially damped oscillations in hard disk fluid occur up to a packing fraction η(∗)∼0.718.
- This value agrees with the fluid-solid transition packing fraction (η∼0.723).
- Exponential damping in hard sphere fluid becomes impossible when λ≥34.81, consistent with prior numerical findings.
Conclusions:
- The study provides a new method for analyzing correlation decay in dense fluids.
- It clarifies the conditions for oscillatory decay in hard disk and sphere systems.
- The method confirms the absence of structural transitions in hard rods across densities below close packing.
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