title: Landau model of the direct isotropic to smectic-C*A phase transition in antiferroelectric liquid crystals.
abstract: An orientational order parameter is proposed for the isotropic to smectic C*A phase transition in antiferroelectric liquid crystals. A phenomenological theory is developed to describe the direct isotropic to smectic-C*A phase transition on the basis of a free energy expansion. The free energy is written in terms of the coupled order parameters including the antipolar correlations. We present a detailed analysis of the different phases that can occur and analyze the question: under which conditions a direct isotropic to smectic-C*A phase transition is possible when compared to other phase transitions? The theoretical results are compared with experimental results.
authors.affiliation: Institute of Physical Chemistry, University of Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany.
authors.forename: Prabir K
authors.initials: PK
authors.lastname: Mukherjee
authors.forename: Frank
authors.initials: F
authors.lastname: Giesselmann