Acetone, addition reactions excited state energies

In addition to solvation free energies, Gao has studied the effects of solvent on the conformational equilibria of different molecules and on the free energy profiles for various reactions, including nucleophilic substitution and pericyclic reactions. Another area he has studied is the effect of solvent on solute molecules in their excited states and, in particular, the shifts that are observed in their spectra in different solvents. The calculations showed that, whereas the blue shifts of acetone arising from stabilization of the ground state in polar solvents could be successfully reproduced, the hybrid potentials could not account for the red shifts which arise in some nonpolar solvents. This is a limitation of the model as the red shifts are caused by changes in the dispersion interactions between the two states and the solvent. ... 

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