Phase transitions and characterization in a chiral Smectic-A _deVries liquid crystal by low-frequency dielectric spectroscopy

Low-frequency (10Hz-6.5MHz) dielectric investigations are carried out in Smectic-AdeVr phase exhibited by a chiral Liquid Crystal molecule viz., TSiKN65F. Phase transition temperature determined by dielectric method agrees with TM and DSC. LF dielectric study revealed two relaxations in [image omitted] phase, i.e., a Low-frequency sluggish LF-mode and a High-frequency fast HF-mode of dipole reorientation. Dynamics estimated through slope of [image omitted](T) infers faster HF-mode by three orders. The Arrhenius shift of HF-mode [image omitted] infers an activation energy of 0.72eV. Influence of field on LF mode is studied. Off-centered dielectric dispersion is analyzed through Cole-Davidson equation. Trends of static permittivity (o), high-frequency permittivity (), dielectric increment , and -parameter studied from Cole-Cole plots are explained.