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Structural transitions in hypersphere fluids: predictions of Kirkwood's approximation
Jarosław Piasecki1, Piotr Szymczak, John J Kozak
1Institute of Theoretical Physics, Faculty of Physics, University of Warsaw, Hoża 69, 00-681 Warsaw, Poland.
This study identifies critical volume fractions for structural transitions in hard sphere systems across multiple dimensions using an analytic criterion. The findings align with numerical simulations, confirming theoretical predictions for phase transitions.
Area of Science:
- Statistical Mechanics
- Condensed Matter Physics
- Computational Chemistry
Background:
- Understanding phase transitions in hard sphere systems is crucial for statistical mechanics.
- Previous work established an analytic criterion for correlation damping.
Purpose of the Study:
- To determine threshold volume fractions for structural transitions in hard sphere systems.
- To investigate these transitions in dimensions D = 3, 4, 5, and 6.
- To explore the high-dimensional limit (D → ∞).
Main Methods:
- Utilizing a previously developed analytic criterion for vanishing exponential damping of correlations.
- Applying the Yvon-Born-Green hierarchy.
- Employing the Kirkwood superposition approximation.
Main Results:
- Threshold volume fractions for structural transitions were determined for D = 3, 4, 5, and 6.
- The theory qualitatively agrees with numerical studies, predicting phase transitions.
- The asymptotic form of the analytic condition for structural transitions in the D → ∞ limit was derived.
Conclusions:
- The analytic criterion effectively predicts phase transitions in hard sphere systems.
- The theoretical framework provides insights into high-dimensional behavior.
- The study validates theoretical predictions against numerical evidence.
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