Landau Model of the Smectic C - Isotropic Phase Transition
نویسندگان
چکیده
We propose a Landau model to describe the smectic C isotropic phase transition. A general Landau theory for the coupled orientational and translational order parameters and including the tilt angle is developed. The conditions for the smectic C isotropic phase transition and the stability conditions of the smectic C phase are calculated. On the basis of this model it is argued that the smectic C isotropic phase transition is always first order. We present a detailed analysis of the question under which conditions a direct smectic C isotropic phase transition prevails in comparison to smectic A isotropic and nematic isotropic transitions. The theoretical results are found to be in qualitative agreement with all published experimental results. Typeset using REVTEX
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