Nematic fluid at a hard wall in the mean field approximation

TL;DR

This paper uses a mean field theoretical approach to analyze the behavior of a nematic fluid near a hard wall, deriving analytical profiles and revealing interface-induced dilution and disorder.

Contribution

It introduces an analytical mean field framework for nematic fluids with Yukawa interactions at interfaces, including contact theorem proof and profile expressions.

Findings

Nematic fluid can be more diluted near the wall.

Order parameter profiles are derived analytically.

Interface effects can reduce local ordering.

Abstract

In the framework of a field theoretical approach we study Maier-Saupe nematogenic fluid in contact with a hard wall. The pair interaction potential of the considered model consists of an isotropic and an anisotropic Yukawa terms. In the mean field approximation the contact theorem is proved. For the case of the nematic director being oriented perpendicular to the wall, analytical expressions for the density and order parameter profiles are obtained. It is shown that in a certain thermodynamic region the nematic fluid near the interface can be more diluted and less orientationally ordered than in the bulk region.