Dielectric investigations on a bent-core liquid crystal

Dielectric measurements on a bent-core liquid crystal were carried out in the frequency range from10 mHz to 100 kHz in planar aligned cells. Four relaxation ranges were detected during heatingcondition: two in a low frequency range of a few hertz probably due to conductivity and interfacerelaxation phenomena, another between 10 and 20 Hz, and another one in a range between 10 kHzand 100 kHz in smectic as in nematic and isotropic phases. The third relaxation response is nomore visible during cooling conditions. Dielectric increments, distribution parameters, andrelaxation frequencies have been evaluated at different temperatures by fitting data with Havriliak-Negami (H-N) relaxation function, which is an empirical modification of the Debye relaxationmodel. The presence of a relaxation response between 10 and 20 Hz and the relatively great valuesof the permittivity could suggest the presence of a ferroelectric response due to the presence ofcybotactic clusters.