Static solvent permittivity electrolyte solutions

Static solution permittivity, e(c), and static solvent permittivity, es(c), for solutions of various electrolytes at various concentrations (c) have been obtained by dielectric relaxation spectroscopy [44]. Ion-pairs contribute to permittivity if their lifetime is longer than their relaxation time. However free ions do not contribute to permittivity. Thus,... 

Dielectric properties describe the polarization, P, of a material as its response to an applied electric field E (bold symbols indicate vectors) [1—3], In the field of solution chemistry, the discussion of dielectric behavior is often reduced to the equilibrium polarization, Pq = So(s — V) Eq (eq is the electric field constant), of the isotropic and nonconducting solvent in a static field, Eq. Characteristic quantity here is the static relative permittivity (colloquially dielectric constant ), , which is a measure for the efficiency of the solvent to screen Coulomb interactions between charges (i.e., ions) embedded in the medium. As such, enters into classical electrolyte theories, like Debye-Hiickel theory or the Bom model for solvation free energy [4, 5] and is used... 

From the preceding relation, it is apparent that 1/k is inversely proportional to the valence Z of the ions in the solution phase and to the square root of their concentrations. It is also directly proportional to the square roots of the absolute temperature and the relative static permittivity (or dielectric constant) of the medium. It is therefore to be expected that in a solvent of high dielectric constant, such as water, electrical effects extend much further into the solution phase than in a solvent of low dielectric constant, such as a hydrocarbon. Also, in the presence of an electrolyte, electrical effects have shorter ranges than in its absence—that is, the electrical double layer is compressed. 

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