Relative permittivity field dependence coefficient

Table 3.7 The relative permittivity field dependence coefficient ie/10"18 V"2 m2...

If the dependence of the relative permittivity of the solvent on the electric field strength of the ions is also taken into account, then other thermodynamic parameters of electrolyte solutions (activity coefficient, heat of dilution, partial molar enthalpy content of the solute etc.) can likewise be calculated in better agreement with the experimental data. Although the introduction of the field-dependent relative permittivity into the ion-ion and ion-solvent interactions is accompanied by very great mathematical difficulties, the problem can be solved successfully by employing various approximations. 

FIGURE 4.1 The relative permittivity of a solvent having a bulk permittivity e(0), a high-field value of the permittivity of (the square of its refractive index), and b coefficient of the field dependence of the permittivity (Eq. 3.16) as indicated, as a function of the distance r/nm from a point charge producing the electric field (From Ref. 12, with permission from the publisher, Wiley). 

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