Dielectric relaxation of chiral octylocyanobiphenyl in racemate sample

The complex electric permittivity of racemate of chiral octyloxycyanobiphenyl (8*OCB) molecules has been studied in the frequency range 0.1 Hz to 0.1 MHz and over a wide temperature range. On cooling the isotropic liquid phase is easily supercooled and below 30 K transforms into glass. On heating a corresponding glass-liquid transition was observed. The dielectric /spl alpha/-relaxation found in supercooled liquid conforms to the Vogel-Fulcher-Tamman equation for the average relaxation time. The Kohlrausch-Williams-Watts function was used to describe the spectral line shape. The molecular dynamics and electric properties of 8*OCB were compared with those of an 8*OCB sample with linear molecules.