Schiff-base coordination complexes with plutonium(iv) and cerium(iv)

Abstract

PuL and CeL (L = N,N'-bis[(4,4'-diethylamino)salicylidene]-1,2-phenylenediamine) have been synthesized, and characterized by single crystal X-ray diffraction, UV/vis/NIR spectroscopy, and cyclic voltammetry. These studies reveal the enhanced stabilization of Pu(iv) versus Ce(iv) with this Schiff base, and quasi-reversible redox behaviour only with the plutonium complex.

Complexation and redox chemistry of neptunium, plutonium and americium with a hydroxylaminato ligand

“…For context with other structurally similar Pu(IV)/Ce(IV) N,O-donor complexes, the Pu-O vs Ce-O and Pu-N vs Ce-N distances in the Schiff-base coordination complexes ML 2 (M = Pu, Ce; L = N,N'-bis[ (4,4'-diethylamino)salicylidene]-1,2-phenylenediamine) were statistically equivalent and also very similar in comparison to the corresponding M-O and M-N hydroxylamide distances after taking standard deviations associated with average values into account. 23 The exact mechanism responsible for obtaining a Pu(IV) complex is not known but is likely driven by the strongly donating hydroxylamine ligand conferring stability to the tetravalent oxidation state. Possible causes are disproportionation of Pu(III) to Pu(0) and 3 equiv Pu(IV) or reaction with the solvent medium.…”

Synthesis, characterization, and high-pressure studies of a 3D berkelium(iii) carboxylate framework material

“…Bk), 23 An III 2 (HPO 3 ) 3 (H 2 O) (An = Pu, Am), 24 and An III 2 (C 4 O 4 ) 3 (H 2 O) 4 (An = Am, Cf). 25 The opposite effect is found in softer donor systems such as An III (dtc) 3 (phen) (dtc À = diethyldithiocarbamate; phen = 1,10-phenanthroline, An = Am, Cm, Cf), 26 [K(crypt)][Pu III (COT) 2 ] (crypt = 2.2.2-cryptand, COT 2À = cyclooctatetrenide), 27 and An IV L 2 (H 2 L = N,N 0 -bis[(4,4 0 -diethylamine)salicylidene]-1,2-phenylenediamine, An = Th, U, Np, Pu) 28,29 where the actinide bond lengths fall significantly below the lanthanide-ligand bond trendline meaning the actinide bond lengths are shorter than expected based on their ionic radii.…”

Thermodynamics of Fluorite-Structured Oxides Relevant to Nuclear Energy: A Review

“…However, thorium only has one stable oxidation state while Pu and U have several. Considering oxidation state as well as the similar ionic radii of tetravalent cerium and plutonium, cerium is a better analogue to plutonium and was studied as an analog to uranium and plutonium. − However, working with depleted uranium avoids problems related to high levels of radioactivity and requires only normal laboratory safety procedures and proper disposal of waste.…”