Expansion of the Na₃M^III(Ln/An)₆F₃₀ Series: Incorporation of Plutonium into a Highly Robust and Stable Framework.

Pace, Kristen A.; Klepov, Vladislav V.; Deason, Travis K.; Smith, Mark D.; Ayer, Gyanendra B.; Diprete, David P.; Amoroso, Jake W.; Loye, Hans‐Conrad

NanMAn6F30 is an extremely versatile framework structure for incorporating tetravalent actinides (An) and cerium along with divalent or trivalent d‐metals (M); moreover, the structure exhibits a high resistance to harsh chemical conditions. This extreme robustness can potentially be exploited for the sequestration of plutonium in a stable matrix; however, no NanMPu6F30 compounds have been reported so far. Herein, we present four new plutonium fluorides that have been prepared as single crystals by mild hydrothermal synthesis methods. Structural characterizations revealed their compositions to be Na3AlPu6F30, Na3FePu6F30, Na3CoPu6F30, and Na2.4Mn1.6Pu6F30. Surprisingly, in the plutonium series, it was found that Co2 and Mn2 precursors oxidized to form Na3CoIIIPu6F30 and Na2.4MnII/III1.6Pu6F30, whereas the analogous reactions for cerium result in reduction of the transition metal, even when beginning with a M3 precursor. While cerium is often used as a surrogate for plutonium, this work serves as an example that deviations between their chemistries do occur.

PLUTONIUM; CHEMICAL resistance; TRANSITION metals; HYDROTHERMAL synthesis; ACTINIDE elements; SINGLE crystals; CERIUM oxides; RARE earth metals

Chemistry - A European Journal, 2020, Vol 26, Issue 57, p12941

0947-6539

Academic Journal

10.1002/chem.202002774