Reentrant Antiferroelectric Phase in 4-(1-Methylheptyloxycarbonyl) phenyl 4'-Octylbiphenyl-4-Carboxylate

The presence of three phases was found between SmA and the antiferroelectric SmC A * phase in optically active ( R )-4-(1-methylheptyloxycarbonyl)phenyl 4'-octylbiphenyl-4-carboxylate. Two of these phases were identified as SmC α * and SmC γ * by the miscibility test. The remaining phase between these was confirmed to be another antiferroelectric phase from dielectric measurement and conoscopic observation. Thus, antiferroelectric order appears at least three times: SmC α * , the new antiferroelectric phase and SmC A * . The new antiferroelectric phase is different from the SmC A * phase in that it exhibits much lower stability against an electric field.