Previous investigations on chiral recognition in photoinduced bimolecular electron transfer (ET) processes were inconclusive because diffusion was the rate-limiting step of the fluorescence quenching. However, measurements with a ~100 fs resolution give access to the static, diffusion-free, stage of the ET quenching. The left figure shows an acceleration of the nanosecond-resolved fluorescence dynamics of a chiral fluorophore (F) upon addition of a chiral electron donor (Q), pointing to an efficient ET quenching. The early dynamics (right panel) are strongly non-exponential and dominated by static quenching. It is the same independent of whether the (+), the (-) or the racemic forms of the fluorophore react with the (-)-form of Q. The absence of chiral recognition has important implications on the mechanism of this widespread reaction.
|FOR MORE INFORMATION|
Physical Chemistry Department - Sciences II - University of Geneva
30, Quai Ernest Ansermet - CH-1211 Geneva 4 (Switzerland)
© All rights reserved by Eric Vauthey and the University of Geneva
Design and code by Guillaume Duvanel