Plenary Lecture. Phase transitions and critical phenomena in polar smectic A liquid crystals

Since the discovery of a phase transition between two polymorphic forms of the smectic A phase, there has been a considerable amount of experimental as well as theoretical work on strongly polar materials exhibiting different smectic A phases. These studies have led to the observation of a variety of new phase transitions and critical phenomena which are rarely encountered in any other area of condensed matter physics. We review briefly some of these important results.