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The density profile of hard sphere liquid system under gravity
1Institute of Theoretical Physics, Shanghai Jiao Tong University, Shanghai 200240, China. moroshine@hotmail.com
The Journal of Chemical Physics
|July 20, 2006
Summary
Density functional theory and Monte Carlo simulations reveal particle interactions significantly alter hard sphere liquid density profiles under gravity, differing from simple barometric distributions and predicting crystallization at system bases.
Area of Science:
- Statistical Mechanics
- Soft Matter Physics
Background:
- Understanding fluid behavior under external fields is crucial.
- Hard sphere liquids offer a fundamental model system.
- Gravity's effect on liquid density profiles requires detailed investigation.
Purpose of the Study:
- To calculate the density profile of hard sphere liquid under gravitational force.
- To compare results from density functional theory (DFT) and Monte Carlo (MC) simulations.
- To establish the validity range of DFT for this system and analyze deviations from standard models.
Main Methods:
- Density functional theory (DFT) calculations.
- Monte Carlo (MC) simulations.
- Comparison of DFT and MC results across various parameters.
Main Results:
- Consistent results obtained from DFT and MC methods over a wide parameter range.
- Established the operational limits for DFT in modeling hard sphere liquids under gravity.
- Observed significant deviations from the barometric height distribution, highlighting particle interaction importance.
- Predicted a crystallization phenomenon in the lower region of the system under strong gravitational fields.
Conclusions:
- Particle interactions are critical in determining density distributions in external fields.
- DFT provides a reliable method for studying such systems within its established validity range.
- Gravitational effects can induce phase transitions, like crystallization, in confined liquids.
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