Lateral Substitution as Effective Tool for Tuning Self-Organising Behaviour of Chiral Mesogens

Abstract

. Thermotropic liquid crystals belong to an exciting class of self-organising materials, which are broadly utilised now, and, definitely will find advanced applications in future. The combination of fluidity and ordering together with specific electro-optical properties assures their extraordinary practical usefulness. How-ever, the molecular structure – mesomorphic property relationship is still far to be well-established and understood despite more than a hundred years of their existence and intensive study. The design, synthesis and investigation of new liquid crystalline materials with various molecular structure type (rod-like, bend-shaped, disc-like, etc.) and weight (low molar mass, macromolecular) still remain an actual and highlighted task. In this mini-review we discuss relatively broad sub-class of chiral calamitic liquid crystalline materials derived from the lactic acid and give some specific examples on effective tuning of their mesomorphic and electro-optical behaviour using various types of lateral substitution of molecular core. Fluorine, chlorine, bromine and iodine atoms, as well as bulky methyl and methoxy groups are used as lateral substituents on the phenyl ring far from the chiral lactate group. The materials discussed in this work can be potentially used as smart dopants for design of advanced multicomponent mixtures targeted for future applications in opto-electronics and photonics.