Lippert, Ernst

The anomalous dual fluorescence emission of p-A V-dimethylamino benzoni-trile (DMABN) in polar solvents was first reported by Ernst Lippert in 1962. Emission spectra of DMABN in solvents of different polarity show a dual emission, where the red-shifted emission is stronger relative to the primary emission when the solvent polarity increases. Furthermore, it can be observed that overall emission intensity is reduced in more polar solvents, but higher solvent viscosity increases the emission intensity. Spectra of DMABN in different solvents are shown in the chapter of Tomin in this book [1]. 

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