Fluorinated Liquid Crystals

Abstract

The element fluorine is essential for the operation of modern liquid crystal displays (LCDs). It is “visible” to billions of people who mostly are unaware of its presence—in the same room, their pockets, and very often close to their faces. Fluorine makes liquid crystals polar, so they can be switched in an electric field. It imparts conformational rigidity, chemical stability, low polarizability, and viscosity—all crucial factors for the smooth operation of the state‐of‐the‐art LCDs. This chapter presents the syntheses and structure–property relationships of a wide variety of fluorinated materials. Their uses range from standard LCDs to yet unrealized technologies such as Blue Phase displays and future applications of the newly discovered ferroelectric nematic phases. The design of new compounds is often based on rational arguments and a detailed analysis of the physical properties expected for a given structural feature. This is then realized by employing sophisticated synthetic methods unheard of in standard materials chemistry. Even after four decades of research, there is still room for fascination, progress, and surprises.