Solvaton model

As for the theoretical treatment, we could only try to include the eleetrostatie solute-solvent interaetions and, in faet, we corrected the electronic potential energies for the solvation effeets by simply adding as calculated according to the solvaton model [eq. (2)]. The resulting potential curves are to be seen as effective potentials at equilibrium, i.e. refleeting orientational equilibrium distributions of the solvent dipoles around the eharged atoms of the solute molecule. In principle, the use of potentials thus corrected involves the assumption that solvent equilibration is more rapid than internal rotation of the solute molecule. Fig. 4 points out the effects produced on the potential... 

In order to take into account the heterogeneous nature of the surroundings around the guest molecule in the a-CD inclusion-complex, a more realistic solvaton model was constructed. It was assumed that the a-CD cavity has the environmental(solvent) effect of dielectric constant on the included part of the guest molecule, while the other part of the guest is exposed to the aqueous layer of dielectric... 

Finally, it should be noted that, from a theoretical point of view, several trends are shown to be satisfactorily reproduced by sum-over-states calculations using INDO/S parameters (A 24). These calculations make use of both the solvaton model to describe the effect of changes in the dielectric constant of the medium, and a dimer model to repre-... 

For nonspecific solvent-solute interactions the solvaton model provides a satisfactory account of nuclear shielding changes (36). As in the reaction field model, the strength of the solvent-solute interaction depends upon the dielectric constant, e, of the medium. 

As in the case of nuclear shielding, the solvaton model has been applied to calculations of spin-spin couplings (19). The reaction field and other similar models have been used, together with INDO-FPT calculations of the contact contribution, to a number of couplings with some success (20). 

Although the calculated variation in J(N=C), as a function of e, is not large, it is comparable to the J(N-C) data for aniline and formaraide which is attributed to specific hydrogen bonding effects. Thus, the nonspecific influences, included in the solvaton model, could be as important as hydrogen bonding, and perhaps conformational effects, on J(N=C). 

Table 4. Results of Some FPT-INDO Calculations, Using the Solvaton Model, of the Effect of the Dielectric (e) of the Medium on Some Values of lj(N=C) in Hz ...

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