Polarization of the medium per unit volume

The total polarization of the medium per unit volume eonsidering also the mole-eular polarizability beeomes... 

The other direction is connected with the work of Libby (1952), who suggested that a considerable part of the Frank-Condon barrier in the reaction is due to the solvent polarization. Since, in the first works of this kind, attention was paid mainly to the role played by the solvent in the reaction and since the solvent was described using the concept of the polarization of the medium per unit volume, theories of this kind are referred to in the literature sometimes as continuum ones (see, e.g.. Ref. 8). 

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