Structures and correlation functions of multicomponent and polydisperse hard-sphere mixtures from a density...

Area of Science:

• Statistical Mechanics
• Soft Matter Physics
• Computational Chemistry

Background:

• Understanding the structural properties of hard-sphere mixtures is crucial in statistical mechanics.
• Existing theories often face challenges in accurately describing both uniform and nonuniform systems.

Purpose of the Study:

• To develop and validate a modified fundamental-measure theory for hard-sphere mixtures.
• To investigate the structure of polydisperse hard-sphere fluids near a hard wall.

Main Methods:

• Modified fundamental-measure theory incorporating Rosenfeld's weight functions and the Boublik-Mansoori-Carnahan-Starling-Leland equation of state.
• Comparison of theoretical predictions with results from molecular dynamics and Monte Carlo simulations.

Main Results:

• Excellent agreement between theoretical predictions and molecular simulations for density profiles, local compositions, and radial distribution functions.
• Successful extension of density functional theory to polydisperse hard-sphere fluids near a hard wall.
• Prediction of oscillatory size segregations in polydisperse hard-sphere fluids.

Conclusions:

• The modified fundamental-measure theory provides a robust framework for studying hard-sphere mixtures.
• Density functional theory accurately captures the behavior of polydisperse systems near interfaces.
• The findings offer insights into phase behavior and structural organization in complex fluids.