Effect of Central Longitudinal Dipole Interactions on Chiral Liquid-Crystal Phases

• Published in: International journal of molecular sciences Vol. 19; no. 9; p. 2715
• Main Authors: Nozawa, Takuma, Brumby, Paul E, Yasuoka, Kenji
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 11.09.2018; MDPI
• Subjects: chirality; Computer simulation; Crystals; dipole; Dipole interactions; Dipoles; Grain boundaries; liquid crystals; Liquid Crystals - chemistry; Liquid phases; Models, Chemical; Molecular Dynamics Simulation; molecular simulation; Monte Carlo Method; Phase Transition; Phase transitions; Physical properties; Static Electricity; Stereoisomerism; Studies; liquid crystals; phase transition; chirality; molecular simulation; dipole
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms19092715

Monte Carlo simulations of chiral liquid-crystals, represented by a simple coarse-grained chiral Gay⁻Berne model, were performed to investigate the effect of central longitudinal dipole interactions on phase behavior. A systematic analysis of the structural properties and phase behavior of both achiral and chiral systems, with dipole interactions, reveals differing effects; strong dipole interactions enhance the formation of layered structures; however, chiral interactions may prevent the formation of such phases under certain conditions. We also observed a short-ranged smectic structure within the cholesteric phases with strong dipole interactions. This constitutes possible evidence of presmectic ordering and/or the existence of chiral line liquid phases, which have previously been observed in X-ray experiments to occur between the smectic twisted grain boundary and cholesteric phases. These results provide a systematic understanding of how the phase behavior of chiral liquid-crystals changes when alterations are made to the strength of dipole interactions.