Results of dielectric constant (e) studies in diethyl ether for the surrounding of the gas – liquid critical point, TC − 130 K TC. For the ultrasound sonicated system, the split into coexisting phases disappeared and dielectric constant approximately followed the pattern of the diameter. This may indicate the possibility of the extension of the “supercritical technology” into the ultrasound “homogenized” subcritical domain: the “strength” and the range of the precritical effect of d(T) are ca. 10× larger than for e (T > TC).

The super- and sub-critical effects for dielectric constant in diethyl ether

A plot is given, showing the result of a scaling analysis of dielectric loss curves containing, apart from low molecular glass former data (glycerol, dibutyl phtalate), also loss curves of the following liquid crystallinematerials, mostly in the isotropic phase: 4-(2-methylbutyl)-4'cyanobiphenyl (5*CB, supercooled isotropic phase), 4-cyano-4-n-alkyl biphenyls (nematogens 5CB and 8CB, isotropic phase), 4-(4-cyano-4-butylcyclohexyl)-4'-octylbiphenyl (laterally substituted nematogen, isotropic phase), and 4-n-alkyl-4'-isothiocyanatobiphenyl (5 and 10 BT, isotropic and SmE phases). The plot applies the scaling formula originally proposed forglassforming, supercooled liquids [Dendzik et al. 7 ]. The result supports the recent suggestion that dielectric relaxation in the isotropic phase of nematogens may show some features typical for "glassy" materials.

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A. Kurbatov

Papers

Universal Scaling of Alpha Relaxation in Complex Liquids