Dielectric Studies of 4-w-Hexyloxy-4'-Cyanobiphenyl (60CB) at Elevated Pressure*
نویسنده
چکیده
The principal dielectric permittivity components in the nematic phase of 4-rc-hexyloxy-4'-cyanobiphenyl (60CB) were measured as functions of temperature at ambient pressure and as functions of pressure up to 100 MPa at several constant temperatures. The dielectric anisotropy is analized in the frame of the Maier-Meier equations. The pressure dependence of the order parameter is deduced. Preliminary results for the activation volume and activation enthalpy from the pressure and temperature dependences of the longitudinal relaxation times are obtained.
منابع مشابه
Dielectric Studies on Liquid Crystals under High Pressure: VI. Low Frequency Relaxation Process in the Nematic and Smectic A Phase of 4-n-Octyl-4'-Cyanobiphenyl (8 CB)
Dielectric relaxation studies of 4-n-octyl-4'-cyanobiphenyl (8 CB) were performed in the pressure range 0 .1 -1 2 0 MPa, the frequency range 1 k H z-1 3 MHz and the temperature range 295-331 K. The dielectric behaviour of 8CB in the nematic phase is similar to that of 5CB, 6CB and 7CB. In particular, the activation enthalpy decreases with increasing pressure and the activation volume decreases ...
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