Phase transition of nematic to smectic C through an intermediate boundary induced smectic A structure

An intermediate phase has been observed at the transition nematic to smectic C where a smectic A structure induced by the boundaries and a nematic phase exist simultaneously. The temperature interval of existence of the intermediate phase is of the order of one tenth of degree. Several conditions are necessary for its appearance: the latent heat L of the phase transition nematic‐smectic C of the liquid crystal should be sufficiently small ( L < k B T c ); the nematic phase should undergo a bend deformation by the boundaries (possibly a twist one as well) and the transition nematic‐smectic C should be carried out as slower as possible.