An international group of scientists, led by the Helmholtz Zentrum Dresden-Rossendorf (HZDR), has discovered a new compound of plutonium with an unexpected, pentavalent oxidation state, utilizing the ESRF, the European Synchrotron, Grenoble, France. This new phase of plutonium is stable and steady, and could also be a transient phase in radioactive waste repositories.
Nations across the planet are making efforts to enhance the safety of nuclear waste storage to stop the release of radioactive nuclides to the environment. Plutonium has been shown to be transported by groundwaters from contaminated sites for kilometers in the form of colloids, which are formed by a mixture of clay, iron oxides, or pure natural matter. A group of scientists led by HZDR reviews the chemistry of actinides under environmentally-related conditions, by synthesizing such compounds, and then studying their electronic and structural behavior with advanced synchrotron X-ray methods experimentally as well as theoretically.
The latest paper of the global team reveals how an experiment seemingly gone wrong results in a breakthrough: the discovery of a brand new stable form of plutonium.
The only method to be certain of the existence of this pentavalent compound can be to confirm it utilizing HERFD at the Pu M4 edge. Kvashnina explains: “Our selection of beamline was simple: the ESRF-ID26 beamline, as it’s the best place, regarding the depth and energy resolution, where such high-power resolution X-ray absorption spectroscopy studies at low energies could be carried out. The Pu M4 edge HERFD experiment was executed at ID26 for the first time.