Tuning density profiles and mobility of inhomogeneous fluids

TL;DR

This study investigates how modifying particle-wall interactions in confined fluids affects their structure and transport properties, revealing that reducing layering can decrease mobility, with excess entropy serving as a predictive tool.

Contribution

It demonstrates the impact of tuning particle-wall interactions on fluid structure and transport, linking layering effects to mobility and entropy.

Findings

Flattening layering reduces fluid mobility.

Enhancing layering can increase mobility.

Excess entropy predicts transport behavior.

Abstract

Density profiles are the most common measure of inhomogeneous structure in confined fluids, but their connection to transport coefficients is poorly understood. We explore via simulation how tuning particle-wall interactions to flatten or enhance the particle layering of a model confined fluid impacts its self-diffusivity, viscosity, and entropy. Interestingly, interactions that eliminate particle layering significantly reduce confined fluid mobility, whereas those that enhance layering can have the opposite effect. Excess entropy helps to understand and predict these trends.