Photophysics of Heterocyclic Dyes

Title

Photophysics of Heterocyclic Dyes

Abstract

The photophysical characteristics of the novel chromophore 1f was studied, and its relation to 1d and 1e of the same class was discussed. Steady-state as well as time-resolved measurements were employed, which showed that this fluorophore possessed a biexponential decay in DMF and MeCN, as well as low quantum yields in all solvents. The biexponential behavior was different from all the other previously investigated chromophores, which all showed mono-exponential decays.

Further investigations with varyring temperature and viscosity showed that a barrier crossing to non-radiative decay was responsible for the low quantum yield, and relatively short lifetime. The activation energy was calculated to 15 kJ/mol in 2-Me THF, with a frequency factor of 1012.

The obtained data are discussed, and possible explanations for the photophysical behavior of these fluorophores is evaluated.

1d (Z=NH2) 1e (OEt) 1f (OH)

Speaker

Jakob Woller