Neptunium Diverges Sharply from Uranium and Plutonium in Crystalline Borate Matrixes: Insights into the Complex Behavior of the Early Actinides Relevant to Nuclear Waste Storage

Abstract

Not like the others: In contrast to uranium and plutonium borates, neptunium borates are mixed-valent and simultaneously display three coordination environments and three oxidation states (see picture; polyhedra: NpIV light blue, NpV dark blue, NpVI green, B yellow; spheres: O red, K or Ba blue).