Bowlic Liquid Crystalsl

Abstract

Abstract A new type of liquid crystals made up of bowl-like molecules was predicted by Lin in 1982 and was recently synthesized. In is paper, the experimental findings about these bowlic mesophases are briefly summarized. Possible mesophases (polar nematic, non-polar nematic, cholesteric, stringbean, donut, columnar, etc.) are proposed and discussed. The possible breakdown of the macroscopic symmetry n → – n (n is the director) in these mesophases is emphasized. Novel properties including phase transitions and other physical aspects (optical, elastic, flexoelectric and hydrodynamic, as well as defects) are presented. Molecular engineering to produce new compounds (e.g. anisotropic ferromagnetic fluid and bowlic polymers) is suggested. Possible instabilities and applications are discussed. The possibility of second harmonic generation and simple sub-microsecond electro-optical switching (without the complications encountered in ferroelectric smectic C*) in these bowlic mesophases are pointed out. These bowlic mesophases may be ferroelectric, antiferroelectric or paraelectric.