The prediction and experimental confirmation of a previously unsuspected kinetic effect occurng in electrolyte solutions are presented herein. Kinetic polarization deficiency may be described as a reduction, with respect to the pure solvent, in the static permittivity of the solution; the decrement in E0 is shown to be proportional to the product of the dielectric relaxation time of the solvent and the low frequency conductivity of the solution. The kinetic ion-solvent interaction affects the capacitive admittance in two closely related ways: as an ion migrates, the surrounding volume elements of the liquid tend to rotate according to the laws of hydrodynamics, and although dielectric relaxation tends to restore an equilibrium polarization appropriate to the local electric field, this adjustment is not instantaneous; rather it lags behind by the dielectric relaxation time. Conversely, the force that an external field exerts on an ion does not develop its full strength instantly because the ion is driven partly by the external field and partly by the polarization that develops in response to the applied field, the polarization field evolving wit a time constant that is the relaxation time for the orientation of solvent dipoles.We wish to report the theoretical prediction and experimental confirmation of an effect occurring in electrolyte solutions for which we have coined the term "kinetic polarization deficiency." For the purpose at hand the phenomenon may be described as a reduction, with respect to the solvent, in the static permittivity of the solution. Assuming, as we shall, a simple Debye dispersion for the dielectric relaxation of the pure solvent, the decrement in Eo will be shown to be proportional to the product of the relaxation time of the solvent TD and the low frequency conductivity of the solution fo.The theoretical framework is as follows: we regard not only the polarization of the vacuum, but also the intrinsic polarization of molecules and ions as occurring on a much shorter time scale than TD, thereby contributing to the high frequency dielectric constant e. On the other hand, since we are concerned only with ion-solvent interactions, the static and kinetic influences on the ionic atmosphere will also be neglected. The model we adopt is that of a symmetrically charged impenetrable sphere (the ion) moving in a viscous, incompressible, polarizble fluid continuum (the solvent) under the influence of a periodic external field. Of course, no continuum model that includes dielectric relaxation can avoid the following inconsistency: that a finite relaxation time implies finite dimensions for a fluid element.If the ion is fixed with respect to the solvent, the latter supports a static polarization field PD, which is the vector sum of the field of the ion Po, plus the image charge-induced polarization emanating from the conducting planes which, we assume, enclose the system. The specification of the compensating image charges is absolutely necessary inasmuch as this insures the convergence of t...

Experimental results are presented for the relative permittivity of several chlorides in water and methanol at 25°C measured at 5-20 MHz up to concentration of 0.1 mol dnr3. These permittivities are interpreted as the static values E' and show in general an initial increase with concentration, followed by a decrease below the static value of the relative permittivity E: of the solvent. The changes in E" with respect to E : are of comparable magnitudz for all chlorides in water at equal equivalent concentration, with a noticeable exception for HQ which exhibits much larger decrements. The decrements in methanol relative to E : are larger than in water. These results for the static relative permittivity of the electrolyte solutions have been shown to be interpretable in terms of a superposition of the Debye-Falkenhagen effect and the kinetic depolarization deficiency recently proposed by Hubbard and Onsager. At concentrations G2.5 x mol dm-3 the observed increments are in fair agreement with the theoretical values according to Debye and Falkenhagen.At higher concentrations the experimental decrements seem to folIow the theoretical relation proposed by Hubbard and Onsager, at least semi-quantitatively, and after correction for the former effect. The dependence of the relative decrements on the specific conductivity of the solution and the dielectric relaxation time of the solvent, predicted by Hubbard and Onsager, has been confirmed. No definite conclusion could be reached as to whether or not the dielectric saturation effect has some influence on the observed decrements.

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The dielectric relaxation behavior of three sodium polyphosphates with different but low degrees of polymerization in aqueous solution (without salt) has been investigated between 8 kHz and 100 MHz. The highest molecular weight sample (DP 338) exhibits two dispersion regions as is generally observed with synthetic polyelectrolytes at higher degrees of polymerization and is interpreted, according to the theory of van der Touw and Mandel, by attributing a certain flexibility to the polymer chain. The experimentally determined relaxation time of the high‐frequency dispersion is in fair agreement with the theoretically calculated value. For the lowest molecular weight sample (DP 112) the experimental results can best be described by a single dispersion curve pointing to a rigid, more or less stretched, conformation of the polyion in agreement with theoretical predictions. For the sample of intermediate molecular weight (DP 198) the situation is borderline as it is possible to describe the relaxation behavior by either one or two dispersion regions; it is, however, concluded from an analysis of the dielectric results that the average conformation is rather extended, but not completely rigid.