| Autor: |
Klamm BE; Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Room 118 DLC, Tallahassee, Florida 32306, United States.; Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87544, United States., Windorff CJ; Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Room 118 DLC, Tallahassee, Florida 32306, United States., Celis-Barros C; Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Room 118 DLC, Tallahassee, Florida 32306, United States., Beltran-Leiva MJ; Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Room 118 DLC, Tallahassee, Florida 32306, United States., Sperling JM; Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Room 118 DLC, Tallahassee, Florida 32306, United States., Albrecht-Schönzart TE; Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Room 118 DLC, Tallahassee, Florida 32306, United States. |
| Abstrakt: |
A pair of neptunium Schiff base coordination complexes, Np VI O 2 L(MeOH) and Np IV L 2 { H 2 L = N , N '-bis[(4,4'-diethylamino)salicylidene]-1,2-phenylenediamine}, have been synthesized and analyzed by several characterization methods including single-crystal X-ray diffraction, electronic absorption, 1 H NMR, cyclic voltammetry, and theoretical interpretation. Structural analysis reveals that Np VI O 2 L(MeOH) and Np IV L 2 are isomorphous with the previously reported U VI O 2 L(MeOH) and M IV L 2 (M = Pu, Ce, U, Th) complexes, respectively, allowing for a direct comparison across the series. The reduction of Np VI O 2 L(MeOH) in situ or direct synthesis from a (Np V O 2 ) + source shows evidence of a pentavalent neptunyl (Np V O 2 L) x n - species as determined by UV/vis/NIR and 1 H NMR spectroscopy. The synthesis of (Np V O 2 L) x n - directly from a (Np V O 2 ) + starting material gives a similar spectrum. Theoretical analysis offers insight into the electronic structure for a better understanding of the bonding patterns and relative stability of the different oxidation states. Computational results show that the Np-L covalent interactions in Np IV L 2 are similar to those in the Np VI O 2 L(MeOH) complex, indicating that neither the presence of the axial oxo ligands nor the oxidation state significantly modify the nature of the Np-L bonds. |
