Smectic A-Smectic C-Hexatic B meeting point at high pressure - A new multicritical point

Abstract

We report the observation of a new multicritical point, namely, the smectic A- smectic C-hexatic B multicritical point. By high resolution studies, the topology of the phase diagram near the multicritical point is compared with that near the meeting point of smectic A-smectic C-crystal B phases. The latter critical point which has been observed for the first time in the P-T plane is characterised as a critical end point. The details of the high resolution data and the differences in the topologies of the two phase diagrams are presented.