%0 Journal Article
%A Greif, Gerlinde
%A Sauerwein, Fynn S.
%A Weßling, Patrik
%A Duckworth, Tamara M.
%A Patzschke, Michael
%A Gericke, Robert
%A Sittel, Thomas
%A März, Juliane
%A Wilden, Andreas
%A Modolo, Giuseppe
%A Panak, Petra J.
%A Roesky, Peter W.
%T 6-(6-Methyl-1,2,4,5-Tetrazine-3-yl)-2,2′-Bipyridine: A N-Donor Ligand for the Separation of Lanthanides(III) and Actinides(III)
%J Inorganic chemistry
%V 63
%N 33
%@ 0020-1669
%C Washington, DC
%I American Chemical Society
%M FZJ-2024-05168
%P 15259–15269
%D 2024
%X Here, we report the synthesis of the 6-(6-methyl-1,2,4,5-tetrazine-3-yl)-2,2′-bipyridine (MTB) ligand that has been developed for lanthanide/actinide separation. A multimethod study of the complexation of MTB with trivalent actinide and lanthanide ions is presented. Single-crystal X-ray diffraction measurements reveal the formation of [Ce(MTB)2(NO3)3], [Pr(MTB)(NO3)3H2O], and [Ln(MTB)(NO3)3MeCN] (Ln = Nd, Sm, Eu, Gd). In addition, the complexation of Cm(III) with MTB in solution was studied by time-resolved laser fluorescence spectroscopy. The results show the formation of [Cm(MTB)1–3]3+ complexes, which occur in two different isomers. Quantum chemical calculations reveal an energy difference between these isomers of 12 kJ mol–1, clarifying the initial observations made by time-resolved laser fluorescence spectroscopy (TRLFS). Furthermore, quantum theory of atoms in molecules (QTAIM) analysis of the Cm(III) and Ln(III) complexes was performed, indicating a stronger covalent contribution in the Cm–N interaction compared to the respective Ln–N interaction. These findings align well with extraction data showing a preferred extraction of Am and Cm over lanthanides (e.g., max. SFAm/Eu = 8.3) at nitric acid concentrations <0.1 mol L–1 HNO3.
%F PUB:(DE-HGF)16
%9 Journal Article
%$ 39101694
%U <Go to ISI:>//WOS:001286247200001
%R 10.1021/acs.inorgchem.4c01793
%U https://juser.fz-juelich.de/record/1029558