Dielectric Dispersion in Ferrielectric Phase of Antiferroelectric Liquid Crystal

We studied the dielectric behavior in the ferroelectric SmC* and ferrielectric SmCγ * phases of the antiferroelectric liquid crystal (R)-1-methylheptyl-4-( 4′′-n-dodecyloxybiphenyl- 4′ carbonoyloxy)-3-fluoro-benzoate. In the SmCγ * phase, 3 dielectric relaxations were recognized in the frequency range under consideration. The 2 relaxation processes at low frequency with high dielectric loss were attributed to azimuthal fluctuation of the molecules around the cone angle ϕ. Those relaxations are investigated as functions of temperature and applied bias electric field. Besides the 2 low-frequency loss processes, one additional loss process with weak intensity was observed.