Coordination Chemistry of Actinides with Imine Ligands
In order to provide reliable safety assessment on the geological repositories for radioactive wastes, it is important to understand fundamental chemical interactions expected in the relevant geological conditions. In this context, this PhD thesis aims to investigate the interaction of earlier actinides (Th, U, Np and Pu) with organic ligands possessing naturally relevant functionalities, such as imines.
The actinide-ligand complexes will be characterized both in the solid state and in solution by a wide variety of analytical techniques available at HZDR-IRE, such as single-crystal X-ray diffraction, powder X-ray diffraction, UV/VIS, IR, NMR, TRLFS, etc. A systematic investigation on a series of complexes with different actinides and different ligands allows us to reveal the correlation between the complex structure and physical/chemical properties, such as the electronic property. This project focuses particularly on the tetravalent state of actinides, which is the most predominant oxidation state under reductive conditions. Therefore, a special care is required to exclude oxygen during the experiments. The model ligands selected for this project are multidentate Schiff base ligands. The structural flexibility and electronic properties at the donor atoms will be manipulated by changing the ligand structure and/or changing substituents. The acquired experimental data will be compared with quantum chemical calculations to gain further insight into the electronic properties of the actinide complexes.
This PhD project is financially supported by the BMBF project "FENABIUM". (No. 02NUK046B)