Interfacial tension of the isotropic--nematic interface in suspensions of soft spherocylinders

TL;DR

This study uses grand canonical Monte Carlo simulations to analyze the isotropic--nematic interface in suspensions of soft spherocylinders, revealing how interfacial tension varies with particle elongation and finite size effects.

Contribution

It provides the first detailed simulation-based analysis of interfacial tension in soft spherocylinder suspensions, including finite size effects and the relation to particle elongation.

Findings

Interfacial tension increases with particle elongation.

Onsager limit is only reached for very large elongations (L/D > 40).

Finite size effects are significant in the measurements.

Abstract

The isotropic to nematic transition in a system of soft spherocylinders is studied by means of grand canonical Monte Carlo simulations. The probability distribution of the particle density is used to determine the coexistence density of the isotropic and the nematic phases. The distributions are also used to compute the interfacial tension of the isotropic--nematic interface, including an analysis of finite size effects. Our results confirm that the Onsager limit is not recovered until for very large elongation, exceeding at least L/D=40, with L the spherocylinder length and D the diameter. For smaller elongation, we find that the interfacial tension increases with increasing L/D, in agreement with theoretical predictions.