Effects of Conformation of Diastereomer Liquid Crystals on the Preference of Antiferroelectricity

We have already synthesized a new type of antiferroelectric liquid crystals (AFLCs) with double stereogenic centers, β-methyl-substituted TFMHPOBC(4-(1-trifluoromethyl-heptyloxycarbonyl)phenyl 4′-octyloxybiphenyl-4-carboxylate) and its analogues, based on α-trifluoromethyl-β-methylcarbinol, and its conformational effects on the antiferroelectricity^[1-5]. Now we report another new type of AFLC and ferroelectric liquid crystals (FLC) with double stereogenic centers bearing β-trifluoromethylcarbinol. which can be regarded as a β-trifluoromethyl-substituted MHPOBC(4-(methylheptyloxycarbonyl)phenyl 4́-octyloxybiphenyl-4-carboxylate) analogue, and examined its properties such as the phase transition. From these results and ab initio calculations using Gaussian 94 program, we conclude that their conformations strongly affect their preference of antiferroelectricity and that the bend-like structure is more essential for the appearance of antiferroelectricity, than the extended-like one.