Computer simulation and solvatochromic studies of the solvation of a betaine in single and mixed solvent systems

Abstract

The solvation of a solvatochromic indicator (MDEC) has been studied in single and mixed solvents by visible absorption spectroscopy and by a compouter-simulation method. The E_T values for the MDEC correlate with the values of solvent docking energy in a similar manner to that observed previously for an alternative solvatochromic pyridinium betaine. The preferential solvation of MDEC in mixed solvents was found to parallel the behaviour of the previously studied pyridinium betaine, thus giving further credence to the application of its E_T values in interpreting the solvent dependence of reaction rate.