Synthesis and Characterization of Tetravalent Actinide Complexes with Nitrogen Donor Ligands

摘要

In contrast to the dominant trivalent state for thelanthanide series (Ln(Ⅲ)), a wide variety of oxidation states(from Ⅱ to Ⅶ) of actinides (An) makes their chemistryintricate but attractive. Especially the early An thorium(Th), uranium (U), neptunium (Np) and plutonium (Pu)form highly charged cations with the oxidation state of four(An~(4+)), which are of particularly interest for thecoordination chemistry due to their strong interaction withligands. Furthermore, the tetravalent oxidation state of theseAn is also preferred under reductive conditions that couldpotentially occur in the environment. Hence, theunderstanding of the interaction mechanisms betweentetravalent An (An(Ⅳ)) and naturally occurring ligands is ofcrucial importance particularly for the safety assessment ofnuclear waste repository.