is financially supported within the 07.2011-10.2019 time period by the Helmholtz Association of German Research Centers (HGF) and the Karlsruhe Institute of Technology (KIT), Faculty of Chemistry and Biosciences, Institute for Nuclear Waste Disposal (INE)
We systematically investigate the electronic and coordination structures of actinide (An) and chemical homologue lanthanide (Ln) systems with novel synchrotron-based high energy resolution X-ray emission/absorption/inelastic scattering techniques. The experimental results are supported by theoretical calculations and simulations with quantum chemical codes. These investigations improve our understanding of An/Ln reactivity in repository systems and waste matrices on a molecular scale and thereby support the reliability of safety case evaluation of the repository long term safety. The elucidation of electronic and coordination structures of, e.g., An/Ln extraction ligand complexes finds on the one hand application in optimization of separation technologies of lanthanide cations from minor actinides (partitioning), while at the same time provides basic insight into structure-reactivity relationships of actinide elements, which is a present scientific frontier.