The smectic A - smectic C phase transition : sense and nonsense

A simple criterion is presented to discriminate between the smectic A-smetic C phase transition and the pseudo- (i.e. non existing) smectic A-tilted smectic A phase transition. This criterion has been used to classify and examine the existing theories for the smectic A-smectic C phase transition Presentation d'un critere simple permettant de distinguer la transition smectique A-smectique C de la pseudotransition smectique A-smectique A incline. Utilisation du critere pour classer et examiner les theories existantes pour la transition smectique A-smectique C