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Vapor-liquid equilibria and cohesive r-4 interactions
1Centre for Computational Innovations, Swinburne University of Technology, P.O. Box 218, Hawthorn, Victoria 3122, Australia.
The Journal of Chemical Physics
|December 2, 2020
Summary
Cohesive r-4 interactions significantly delay vapor phase emergence, increasing critical temperatures up to fivefold for the n-4 potential. This impacts vapor-liquid equilibria in non-conventional materials.
Area of Science:
- Thermodynamics
- Statistical Mechanics
- Materials Science
Background:
- Understanding vapor-liquid equilibria is crucial for chemical engineering and materials science.
- Cohesive interactions significantly influence fluid phase behavior.
Purpose of the Study:
- Investigate the impact of cohesive r-4 interactions on vapor phase existence and vapor-liquid equilibria.
- Analyze the n-4 potential's influence on critical temperature and phase behavior.
Main Methods:
- Molecular simulations were performed using the n-4 potential.
- Systematic variation of the 'n' parameter in the n-4 potential.
Main Results:
- Cohesive r-4 interactions delay vapor phase emergence to higher temperatures.
- Critical temperatures were observed to be up to 5 times higher than for Lennard-Jones fluids.
- The 5-4 potential showed the greatest influence on vapor-liquid equilibria.
Conclusions:
- The n-4 potential offers insights into materials with low vapor pressure at high temperatures and dipolar interactions.
- A relationship between critical and Boyle temperatures aids in predicting critical temperature for specific n values.
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