Linear and Non-Linear Electro-Optic Studies of the Smectic-A - Smectic-Cα* Phase Transition

Electro-optical measurements have been performed around the SmA-SmCα*phase transition point in antiferroelectric liquid crystals MHPOBC and MHPOCBC. In both materials the soft mode condensation is clearly seen in addition to the partial softening of the ferroelectric soft mode. The Curie Weiss law is observed. The comparison of the slopes of these modes shows that MHPOBC and MHPOCBC should be close to the critical point. In addition to these soft modes, a low frequency mode was detected. © 2001 OPA (Overseas Publishers Association) N.V. Published by license under the Gordon and Breach Science Publishers imprint, a member of the Taylor & Francis Group,.