TY  - JOUR
A1  - Haubitz, Toni
A1  - Tsushima, Satoru
A1  - Steudtner, Robin
A1  - Drobot, Björn
A1  - Geipel, Gerhard
A1  - Stumpf, Thorsten
A1  - Kumke, Michael Uwe
T1  - Ultrafast Transient Absorption Spectroscopy of UO(2)(2+)and [UO2Cl](+)
T2  - The journal of physical chemistry : A, Molecules, spectroscopy, kinetics, environment & general theory
N2  - For the only water coordinated "free" uranyl (VI) aquo ion in perchlorate solution we identified and assigned several different excited states and showed that the (3)Delta state is the luminescent triplet state from transient absorption spectroscopy. With additional data from other spectroscopic methods (TRLFS, UV/vis) we generated a detailed Jablonski diagram and determined rate constants for several state transitions, like the inner conversion rate constant from the (3)Phi state to the (3)Delta state transition to be 0.35 ps(-1). In contrast to luminescence measurements, it was possible to observe the highly quenched uranyl(VI) ion in highly concentrated chloride solution by TAS and we were able to propose a dynamic quenching mechanism, where chloride complexation is followed by the charge transfer from the excited state uranyl(VI) to chloride. This proposed quenching route is supported by TD-DFT calculations.
Y1  - 2018
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/52016
SN  - 1089-5639
VL  - 122
IS  - 35
SP  - 6970
EP  - 6977
PB  - American Chemical Society
CY  - Washington
ER  -