Visible-NIR absorption spectroscopy study of the formation of ternary plutonyl(vi) carbonate complexes

Abstract

We present the first experimental evidence for the ternary complexation of calcium and magnesium ions with plutonyl(VI) tricarbonate species in carbonate-containing aqueous solutions using visible-NIR spectrophotometric titration. Prior to studying...

A spectrophotometric study of the impact of pH and metal-to-ligand ratio on the speciation of the Pu(vi)-oxalate system

“…Only one spectroscopic study of the Pu( vi )-oxalate system has been reported, 20 so additional guidance for understanding changes in our systems was obtained from previous reports on the spectral impact of changing Pu( vi ) coordination. 39–45…”

“…Only one spectroscopic study of the Pu(VI)-oxalate system has been reported, 20 so additional guidance for understanding changes in our systems was obtained from previous reports on the spectral impact of changing Pu(VI) coordination. [39][40][41][42][43][44][45] The peaks at 839 and 846 nm were determined to represent Pu(VI)-oxalate complexes that shared the pentagonal bipyramidal coordination environment of the fully hydrated Pu(VI)-aquo ion ([PuO 2 (H 2 O) 6 ] 2+ ). 47 The strong peaks in the 830-850 nm region were lost as the f-f transition became Laporte forbidden with the addition of an inversion center (i.e., hexagonal bipyramidal coordination).…”