Theory of the dielectric susceptibility of liquid crystals with bent-core molecules

TL;DR

This paper develops a statistical mean-field theory to analyze the dielectric susceptibility and phase behavior of polar liquid crystals with bent-core molecules, predicting a rich phase diagram with four distinct phases and critical points.

Contribution

It introduces a theoretical framework for the dielectric properties of bent-core liquid crystals, extending the Maier-Saupe approach to include complex phase transitions.

Findings

Predicted four phases: isotropic, uniaxial nematic, uniaxial ferroelectric, biaxial ferroelectric.

Calculated temperature dependence of order parameters and susceptibilities.

Identified four critical points in the phase diagram.

Abstract

Statistical theory of the dielectric susceptibility of polar liquid crystals is proposed. The molecules are calamitic or bent-core but the permanent dipole moment is perpendicular to the molecule long axis. The ordering of the phase is described by means of the mean-field theory based on the Maier-Saupe approach. The theory is used to calculate the temperature dependence of the order parameters and the susceptibilities. The phase diagram with four phases is obtained: isotropic, uniaxial nematic, uniaxial ferroelectric, and biaxial ferroelectric. Four critical points are predicted.