Molecular simulation of hierarchical structures in bent-core nematic liquid crystals

The structure of nematic liquid crystals formed by bent-core mesogens (BCMs) is studied in the context of Monte Carlo simulations of a simple molecular model that captures the symmetry, shape and flexibility of achiral BCMs. The results indicate the formation of (i) clusters exhibiting local smectic order, orthogonal or tilted, with strong in-layer polar correlations and anti-ferroelectric juxtaposition of successive layers and (ii) large homochiral domains through the helical arrangement of the tilted smectic clusters, whilst the orthogonal clusters produce achiral (untwisted) nematic states. 1 Phase polymorphism is quite common for solids and rather rare for single-component isotropic liquids. The few known instances of liquid-liquid phase transitions are interpreted in terms of changes in the local molecular arrangement and/or molecular association [1]. In macroscopically uniform nematic fluids, on the other hand, the existence of positionally structured domains, known as cybotaxis [2], is not uncommon and is usually attributed to pretransitional fluctuations. Recently, however, it is becoming apparent that, for a class o