Advances in Microwave and Submillimeter-Wave Dielectric Spectroscopic Techniques and their Applications

Full band spectroscopic studies on the molecular mobility of diluted alcohols

Abstract Static permittivity has been determinded for pure n-decanol and cyclohexanol and their solutions in cyclohexane up to very dilute solutions, the dipole moment is found to decrease with the increase in concentration to a minimum, then it increases continuously. At a certain concentration range, no effect of temperature on the measured dipole moments could be observed, within the observed temperature interval. The dielectric loss was measured in the frequency range from o.1 GHz to 670 GHz. The data are analysed in several Debye and Frohlich terms and the results are discussed.

Disordered charge distributions and dielectric loss in extra dense flint glasses

The complex permittivities of some extra dense flint glasses (EDF glasses) have been studied. The dielectric features of the samples are dominated by their PbO content. Both refractive indices and dielectric losses exhibit a close relation to the concentration of Pb ions. The latter are located either at sites of the network atoms or filling the potential minima interstitially. They can be identified by their different relaxation mechanisms. The dispersion in the submillimeter wave and FIR area is characterized by a very broad distribution of comparably sharp resonant states. “Thermal lens” — or hysteresis effects can be excluded.

Dielectric spectroscopy and molecular dynamics of methylene chloride CH2Cl2

Abstract Precise measurements of the complex permittivity of methylene chloride (CH 2 Cl 2 ) at 293 K have been made at frequencies in the range 50–310 GHz. These, when combined with earlier results, have made possible a determination of the complex permittivity over the entire zero to THz frequency region. These results show a distribution of dielectric relaxation times. The value of the Cole-Cole distribution parameter, α, was 0.03 and that of the relaxation time, τ, was 2.07 ps. A comparison of the power absorption, A (ω), spectra of pure methylene chloride with the normalized dilute solution spectra shows that: (a) the integrated absorption intensity of the pure liquid is 20% greater th…