A quantum chemical approach to dielectric solvent effects in molecular liquids

Abstract The SCF equations for a system of electrons and nuclei surrounded by a dielectric continuum are derived by using a multipolar expansion of the interaction energy The system is used as a model for the dielectric solvent effect. The case of a series of fluorinated is treated as an example in the CNDO/2 approximation. Ethyl fluoride and 1,1,1-trifluoroethane illustrate the importance of the moments other than the dipole one. The solvent effects on conformational equilibria of 1,2-difluoro, 1,1,2,2-tetrafluro, and 1,1,2-trifluoroethane are in reasonable agreement with other data owing to experimental incertainties.

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