A Possible Second Dielectric Dispersion Region in Polar Liquids

Measurements of the complex permittivity of 1 M proline and 1 M hydroxyproline solutions have been made between 300 and 2000 Mc/s and of 3 and 6 M proline solutions between 80 and 2000 Mc/s at a number of temperatures between 0 and 50°C. Considerable dispersion is observed in all cases and the shift of the dispersion region to longer wavelengths with concentration enables the central regions of very large dispersions to be observed for the 3 and 6 M proline solutions. The method of interpretation is as used for ɛ -aminocaproic acid solutions in paper I.

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Dielectric dispersion in pure polar liquids at very high radio-frequencies II. Relation of experimental results to theory

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1952.0139 ◽

1952 ◽

Vol 213 (1115) ◽

pp. 473-492 ◽

Cited By ~ 84

Keyword(s):

Relaxation Time ◽

Viscous Flow ◽

Frequency Factor ◽

Dielectric Dispersion ◽

Resonance Absorption ◽

Millimetre Wave ◽

Polar Liquids ◽

Single Relaxation Time ◽

Observed Behaviour ◽

Very High

The results of the measurements at centimetre and millimetre wave-lengths on the dielectric properties of water, methyl alcohol and ethyl alcohol described in part I are analyzed. There is no evidence that, for any of these liquids, more than a single relaxation time as a function of temperature is required to account for the dispersion arising from dipole rotation. It is suggested that the observed behaviour of the two alcohols at wave-lengths near to 1 cm, which appears not to conform with the hypothesis of a single relaxation time, is in fact the consequence of resonance absorption. If it is supposed that in dipole rotation and viscous flow the molecules have to surmount potential energy barriers, then it appears that, in each of the liquids examined, the heights of the barriers concerned in the two processes are identical; but the ‘frequency factor’ associated with such processes is much larger for viscous flow than for dipole rotation.

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Dielectric dispersion in pure polar liquids at very high radio frequencies - III.The effect of electrolytes in solution

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1952.0187 ◽

1952 ◽

Vol 214 (1119) ◽

pp. 531-545 ◽

Cited By ~ 68

Keyword(s):

Sodium Chloride ◽

Ionic Conductivity ◽

Aqueous Solutions ◽

Methyl Alcohol ◽

Dielectric Dispersion ◽

Basic Theory ◽

Polar Liquids ◽

Polar Dielectric ◽

Radio Frequencies ◽

Very High

A description is given of measurements at millimetre and centimetre wave-lengths of absorption in electrolytic solutions, up to concentrations of about 3 normal, with water and methyl alcohol as solvents. The observations are analyzed in terms of Debye’s basic theory of dispersion in a polar dielectric, and it is shown what modifications to the theory are necessary to take account of the ionic conductivity produced by an electrolyte. Measurements on aqueous solutions of sodium chloride are discussed in relation to Hückel’s theory of electrolytic solutions.

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Main Dielectric Dispersion Region of Mixtures of some Long-Chain Alcohols with Non-Polar Solvents

Zeitschrift für Naturforschung A ◽

10.1515/zna-1972-8-936 ◽

1972 ◽

Vol 27 (8-9) ◽

pp. 1363-1367 ◽

Cited By ~ 1

Author(s):

F. F. Hanna ◽

I. K. Hakim

Keyword(s):

Dielectric Constant ◽

Dielectric Loss ◽

Dipole Moments ◽

Relaxation Times ◽

Dielectric Dispersion ◽

Concentrated Solutions ◽

Polar Solvents ◽

Dispersion Region ◽

Long Chain

Abstract The dielectric constant ε' and dielectric loss ε" are measured for concentrated solutions of n-dodecanol and n-octanol with five non-polar solvents at five frequencies between 2 and 400 MHz at three temperatures between 20 and 60 °C. The effective dipole moments have been calculated and found to decrease with increasing dilution. The relaxation times of the concentrated solutions are lower than that of the pure alcohols, decrease with dilution and are dependent on the nature of the non-polar solvents.

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Dielectric dispersion in pure polar liquids at very high radio-frequencies I. Measurements on water, methyl and ethyl alcohols

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1952.0134 ◽

1952 ◽

Vol 213 (1114) ◽

pp. 400-408 ◽

Cited By ~ 86

Keyword(s):

Refractive Index ◽

Absorption Coefficient ◽

Radio Frequency ◽

Freezing Point ◽

Dielectric Dispersion ◽

Wave Guide ◽

Electrical Characteristics ◽

Polar Liquids ◽

Radio Frequency Energy ◽

Very High

The results are given of some measurements of the absorption coefficient and refractive index of water, methyl and ethyl alcohols at wave-lengths of 6·2 mm, 1·24 cm and 3·21 cm over the temperature range —10 to 50°C, including some observations on water in the supercooled state. The method used is based upon the fact that the rate of attenuation of radio-frequency energy along a wave-guide filled with the liquid is dependent upon both the absorption coefficient and the refractive index when the guide is operated near to the cut-off condition. The electrical characteristics of water vary in a continuous manner through the normal freezing-point of 0°C down to at least —8°C. The measurements indicate that both alcohols, like water, have relatively high atomic polarizations.

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