Molecular orientational reordering and the transformation of a landau second order phase transition to first order in a nematic liquid crystal

Abstract

We consider the nature of the nematic to isotropic phase transition in terms of the molecular orientational reoredering, expressed by the variation of the order parameter s, in the light of Landau's theory of second order phase transition. Then, we show how the de Gennes modification to the Landau thermodynamic potential converts the transition to first order which is in better agreement with the experimental observations.