| Abstract: | The Silberstein models for computing the main polarizabilities of polyatomic molecules are discussed. They apparently constitute the simplest sufficient approach to account for experimental data and assimilate the atoms' electronic surroundings to mutually interacting conducting polarizable spheres. If it is supposed the spheres are centered on the nuclei of the corresponding atoms, interesting but poor results are obtained. More complicated calculations, modifying the center's localisation according to physicochemical evidences, show that a very good estimation of average polarizabilities and anisotropies can be achieved, assuming that in a given molecule the spheres associated to two bounding atoms are tangential and that their polarizabilities are the third power of their proper radius. This “geometrically improved” Silberstein model is compared to the quantum mechanical and “optic valence” models as well as to the other lately used Silberstein models: we put forward its interest and possibilities in relating structure and reactivity, or structure and stability. |
