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](+) JF - 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 U6 - https://doi.org/10.1021/acs.jpca.8b05567 SN - 1089-5639 VL - 122 IS - 35 SP - 6970 EP - 6977 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Müller, Katharina A1 - Foerstendorf, Harald A1 - Steudtner, Robin A1 - Tsushima, Satoru A1 - Kumke, Michael Uwe A1 - Lefèvre, Grégory A1 - Rothe, Jörg A1 - Mason, Harris A1 - Szabó, Zoltán A1 - Yang, Ping A1 - Adam, Christian K. R. A1 - André, Rémi A1 - Brennenstuhl, Katlen A1 - Chiorescu, Ion A1 - Cho, Herman M. A1 - Creff, Gaëlle A1 - Coppin, Frédéric A1 - Dardenne, Kathy A1 - Den Auwer, Christophe A1 - Drobot, Björn A1 - Eidner, Sascha A1 - Hess, Nancy J. A1 - Kaden, Peter A1 - Kremleva, Alena A1 - Kretzschmar, Jerome A1 - Krüger, Sven A1 - Platts, James A. A1 - Panak, Petra A1 - Polly, Robert A1 - Powell, Brian A. A1 - Rabung, Thomas A1 - Redon, Roland A1 - Reiller, Pascal E. A1 - Rösch, Notker A1 - Rossberg, André A1 - Scheinost, Andreas C. A1 - Schimmelpfennig, Bernd A1 - Schreckenbach, Georg A1 - Skerencak-Frech, Andrej A1 - Sladkov, Vladimir A1 - Solari, Pier Lorenzo A1 - Wang, Zheming A1 - Washton, Nancy M. A1 - Zhang, Xiaobin T1 - Interdisciplinary Round-Robin Test on molecular spectroscopy of the U(VI) Acetate System JF - ACS omega / American Chemical Society N2 - A comprehensive molecular analysis of a simple aqueous complexing system. U(VI) acetate. selected to be independently investigated by various spectroscopic (vibrational, luminescence, X-ray absorption, and nuclear magnetic resonance spectroscopy) and quantum chemical methods was achieved by an international round-robin test (RRT). Twenty laboratories from six different countries with a focus on actinide or geochemical research participated and contributed to this scientific endeavor. The outcomes of this RRT were considered on two levels of complexity: first, within each technical discipline, conformities as well as discrepancies of the results and their sources were evaluated. The raw data from the different experimental approaches were found to be generally consistent. In particular, for complex setups such as accelerator-based X-ray absorption spectroscopy, the agreement between the raw data was high. By contrast, luminescence spectroscopic data turned out to be strongly related to the chosen acquisition parameters. Second, the potentials and limitations of coupling various spectroscopic and theoretical approaches for the comprehensive study of actinide molecular complexes were assessed. Previous spectroscopic data from the literature were revised and the benchmark data on the U(VI) acetate system provided an unambiguous molecular interpretation based on the correlation of spectroscopic and theoretical results. The multimethodologic approach and the conclusions drawn address not only important aspects of actinide spectroscopy but particularly general aspects of modern molecular analytical chemistry. Y1 - 2019 U6 - https://doi.org/10.1021/acsomega.9b00164 SN - 2470-1343 VL - 4 IS - 5 SP - 8167 EP - 8177 PB - American Chemical Society CY - Washington ER -