Solvent effects on excited state relaxation phenomena
Solvent effects on excited state relaxation phenomena in binary solvent mixtures, studied by steady state and time-resolved fluorescence spectroscopy, are discussed in the frame oE electrostatic interactions, preferential solvation, weak associations with defined stoichiometry and structure and strongly bonded ground and excited state complex formation. It is shown, that effects of hydrogen bonded complex formation can be discriminated from unspecific interactions in hydrocarbon - hydroxylic binary solvent mixtures. The structure of such complexes and their role in altering excited state proces~cs is discussed for some hydroxy- and amino- compounds (phenols, anilines, aliphatic tertiary amines, and aminmumarins etc.).