Dielectric properties of bent-core nematic materials

We report of dielectric spectroscopy measurements on bent-core nematic liquid crystals. The components of the relative dielectric permittivity and the dielectric loss have been measured as functions of frequency and temperature in the case of various bent-core mesogens in their nematic and isotropic phases. The results show that these liquid crystals have extraordinary dielectric behaviors if we compare them to the traditional calamitic materials, such as -- they show low frequency ( $<$ 10 kHz ) relaxations. Distortion elastic constants measurements reveal that K$_{1}$ / K$_{3} \quad \sim$ 1 in contrast to typical calamitics. The reasons for these anomalous behaviors will be discussed.