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Weighted correlation approach: an extended version with applications to the hard-sphere fluid
1Department of Chemical Engineering and Technology, Royal Institute of Technology, S-100 44 Stockholm, Sweden. zhaow@kth.se
Summary
This study extends the weighted correlation approach (WCA) for inhomogeneous fluids, enabling accurate predictions of hard-sphere fluid density profiles. The enhanced WCA shows good agreement with simulations and fundamental measure theory.
Area of Science:
- Statistical Mechanics
- Physical Chemistry
- Computational Fluid Dynamics
Background:
- Density functional theory (DFT) is crucial for understanding inhomogeneous fluids.
- Existing methods require approximations for direct correlation functions.
- The weighted correlation approach (WCA) offers a framework for these calculations.
Purpose of the Study:
- To extend the weighted correlation approach (WCA) for inhomogeneous fluids.
- To develop a generic expression for the single-particle direct correlation function.
- To apply the extended WCA to predict density profiles of hard-sphere fluids.
Main Methods:
- Developed a generic expression for the single-particle direct correlation function using weighted pair direct correlation functions.
- Applied approximations for pair direct correlation functions and defined weighted densities.
- Utilized density functional theory methods for predicting fluid density profiles.
Main Results:
- The extended WCA accurately represents hard-sphere density distributions, showing good agreement with Monte Carlo simulations.
- WCA results align well with calculations from fundamental measure theory.
- Thermodynamic self-consistency was confirmed through surface tension calculations.
Conclusions:
- The extended WCA provides a robust method for investigating inhomogeneous fluids, including ionic hard-sphere systems.
- This approach facilitates comparison between different DFT strategies.
- The WCA can be effectively applied to predict fluid behavior in confined geometries.
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