Yvon modification

In atomic and simple molecular liquids, the Kerr effect, electric saturation, etc., are caused not only by non-linearities directly induced in the atoms and molecules by the external electric field (the Voigt effect), but are primarily due to Yvon-Kirkwood fluctuational-statistical processes. One should keep in mind, however, that the intrinsic electric polarizability of non-dipolar molecules is subject to modification by at least three factors (i) the effect of translational fluctuations, (//) intermolecular attractive or repulsive forces, and (in) non-linearities induced by the tenq>oraIly and spatially fluctuating electric fields of neighbouring molecules. Thus, the Yvonr-Kirkwood process discussed in Section 4 leads, in dipolar approximation, to the following variation of the electric polarizability tensor of a molecule immersed in a statistically noit-uniform medium ... 

The Born-Green-Yvon (BGY) integral equation approach was used [16] for dilute electrolyte solution, with a modification which ensures electroneutrality (BGY-i-EN). Ions were taken as hard charged spheres of the same diameter, corresponding to the closest ionic approach distance and to twice the closest approach distance to the interface (restricted pritive model, see Figure 2.5). 

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