Coordination Structures of Uranium(VI) and Plutonium(IV) in Organic Solutions with Amide Derivatives.

Carbamide and monoamide derivatives are very promising molecules to achieve U(VI) and Pu(IV) extraction and separation from spent nuclear fuels through solvent extraction. Herein, coordination structures of U(VI) and Pu(IV) complexes with carbamide derivatives were characterized using X-ray crystallography as well as infrared, UV-visible, and EXAFS spectroscopies. Coordination structures are compared to those obtained for monoamide derivatives in order to better understand the role of coordination chemistry in extraction properties.