Computer simulation of chiral liquid crystal phases VIII. Blue phases of the chiral Gay-Berne fluid

Abstract

The phase diagram of chiral calamitic liquid crystals was studied in the temperature-chirality parameter plane by means of computer simulation. Bulk systems composed of N = 2048 uniaxial chiral calamitic Gay-Berne molecules, i.e. with interactions described by the Gay-Berne potential and an additive term for the energy of the chiral interaction, were investigated using Monte Carlo (MC) simulations in the canonical ensemble (NVT). A rich polymorphism of chiral liquid crystal phases was observed along an isotherm with increasing chirality parameter describing the strength of the chiral interaction. In addition to the cholesteric phase (N*), for the first time a blue phase I (BP I) could be proven by computer simulation of a many-particle system based on model intermolecular interactions. Additionally, at high values of the chirality parameter, a phase with randomly oriented squirming double twist tubes was found as characteristic for the so-called spaghetti model for blue phase III (BP III). The structures of all phases were characterized by order parameters, a set of scalar and pseudoscalar orientational correlation functions, and especially by visual representations of selected configurations.