Electron transfer quenching of rhodamine-6G in polymer films.

Electron transfer quenching of the fluorescence of rhodamine-6G in polyvinyl acetate and poly-α-methylstyrene films by aromatic amine quenchers has been examined, using both steady-state and time-resolved methods. Observed quencher concentration dependences do not conform to expectations from either the simple Perrin or Stern–Volmer models. The steady-state quenching results are consistent with long-range electron (tunnel) transfer, with collective quenching at higher quencher concentration, but existing models of this process do not quantitatively rationalize our results. Some potential difficulties with these models are accordingly discussed. Time-resolved (streak camera) experiments confirm that all the quenching events are of dynamic origin, to the exclusion of the involvement of a fractional population of fluorescence-inactive absorbers owing to ground-state complex formation. [ABSTRACT FROM AUTHOR]