Scientific article

Heavy Atom Effect on the Charge Recombination Dynamics of Photogenerated Geminate Ion Pairs

Published inThe journal of physical chemistry. A, vol. 107, no. 31, p. 5894-5902
Publication date2003

The charge recombination dynamics of geminate ion pairs formed by electron transfer quenching of cyanoanthracene derivatives by bromo- and iodo-anisole in acetonitrile was investigated using various ultrafast spectroscopic techniques. Without a heavy atom, the only charge recombination pathway is that leading to the neutral ground state. With heavy atom substituted anisoles, charge recombination to the local triplet state of the excited precursor is observed. Time constants for triplet charge recombination ranging from 400 ps to less than 10 ps, depending on the heavy atom and on the energy gap between the ion pair and the triplet state, have been measured. This heavy atom effect was observed with ion pairs formed upon electron-transfer quenching with driving force going from −0.15 to −0.6 eV, suggesting that these intermediates are in fact exciplexes. A new scheme for producing free ions with a high yield using this effect and a secondary electron donor is also demonstrated.

Research group
Citation (ISO format)
NICOLET, Olivier, VAUTHEY, Eric. Heavy Atom Effect on the Charge Recombination Dynamics of Photogenerated Geminate Ion Pairs. In: The journal of physical chemistry. A, 2003, vol. 107, n° 31, p. 5894–5902. doi: 10.1021/jp0276247
ISSN of the journal1089-5639

Technical informations

Creation09/21/2009 4:22:05 PM
First validation09/21/2009 4:22:05 PM
Update time03/14/2023 3:14:00 PM
Status update03/14/2023 3:14:00 PM
Last indexation05/02/2024 11:17:51 AM
All rights reserved by Archive ouverte UNIGE and the University of GenevaunigeBlack