A detailed study of the dynamics of electro-optical response has been carried out over the whole temperature range of the antiferroelectric $B_2$ phase of a compound with bent-core shape molecules, a homolog $\mathrm{}(n=14\mathrm{})\mathrm{}$ of the series 4-chloro-1,3-phenylene bis[4-(4-$n$-alkylphenylimino)benzoates]. Two types of stripe domains were observed with opposite handedness and simultaneous clock and anticlock motion of the director in the neighboring domains. The temperature dependence of the interlayer potential has been found from the threshold of the transition from the ground antiferroelectric (AF) state to the field-induced ferroelectric (F) state. The rotational viscosity ${\gamma }_{\phi }$ has been calculated from the dynamics of the field-induced azimuthal director switching between F-F and AF-F states and free relaxation of the director from F to AF state. The electro-optical response was also observed below the AF-F threshold. The latter was attributed to the soft-mode distortion of the molecular tilt angle in the vicinity of the transition from the $B_2$ phase to the isotropic phase.

• Received 16 April 2002

DOI:https://doi.org/10.1103/PhysRevE.67.021706