NOVEL TYPE OF ANTIFERROELECTRICITY IN THE HEXATIC SMECTIC I-A-ASTERISK PHASE

In the binary system of MHPOBC and another antiferroelectric liquid cr ystal, we have confirmed that not only the antiferroelectric smectic I -A (SIA*) phase but also the ferroelectric smectic I* (SI*) phase som etimes emerges below the antiferroelectric smectic C-A phase, and tha t even the phase transition from SIA to SI* may occur on cooling. The results have been discussed in connection with the origin of SIA ant iferroelectricity, i.e. a group of transverse dipoles interacting with one another between adjacent layers.