Ferroelectricity, SSFLC, bistability and all that

Abstract

In the book "Ferroelectric and Antiferroelectric Liquid Crystals" by S. T. Lagerwall, the concept "polar liquid crystals" is proposed for the concept earlier known as "ferroelectric liquid crystals", reserving the word "ferroelectric liquid crystals" for the case of "surface stabilization". Thus Lagerwall in this way, by redefinition, becomes the coinventor of "ferroelectric liquid crystals". The trouble is that a closer look on the invention reveals a state of bad logic and a total confusion. The concepts "polar", "ferroelectric", "hysteresis", "SSFLC" and "bistability" are essential in the writing of Lagerwall, but these words are not used in a rigorous way. Also the pictorial evidence used by Lagerwall to illustrate the discovery of surface stabilized liquid crystals raises several questions. An alternative view of the physics of SSFLC cells is presented.