CRITICAL REGION OF THE NEMATIC-ISOTROPIC PHASE-TRANSITION IN THE EPSILON EXPANSION

The phase transition from isotropic liquid to nematic liquid crystal is a weak first-order one. We investigate the possibility of the critical region at the first-order transition line of the nematic-isotropic phase transition in the context of epsilon (epsilon) expansion. We also investigate how the Landau-de Gennes theory of the nematic-isotropic phase transition may break down at a first-order transition. When the nematic-isotropic transition temperature T-NI is inside a critical region, we find that the critical indices of the absolute stability limit of the nematic phase are beta(1)=beta (critical index of the critical point) and alpha(1)=gamma(1)=1-beta.