Modulated Hexatic-B* with giant electroclinic effect rather than anticlinic Hexatic-IA* —A novel mechanism for stabilizing antiferroelectricity below Smectic-CA*

摘要

The antiferroelectric hexatic phase observed below antiferroelectric SmCA* has so far been considered to have the same anticlinic structure as in SmCA*. The orientational order parameter determined by infrared spectroscopy distinctively disproves the previous view and concludes that molecular long axes are not tilted from the SmA layer normal. The phase can be identified as non-tilted modulated HxB* and the electric-field–induced phase transition from this phase to tilted ferroelectric HxI* can be considered as the giant electroclinic effect due to the opening of closed modulation loops.