Plutonium Chemistry by Innovative Synchrotron Methods

Over the past several years, our understanding of plutonium chemistry at the atomic level was greatly improved. This is partly due to the expansion of advanced analytical techniques, developed at the large-scale synchrotron facilities, which recently become available for the investigation of radioactive materials. This contribution will give an overview of those experimental methods available at various synchrotrons and applicable to studying physico-chemical processes of radionuclides behaviour in the environment.

I will mainly focus on high energy resolution fluorescence detected (HERFD) X-ray absorption spectroscopy and Resonant Inelastic X-ray Scattering (RIXS) methods1, which probe the local and electronic structure of actinide materials at the L3 and M4 actinide absorption edges. HERFD and RIXS techniques have high sensitivity towards oxidation state detection and can provide unprecedented information on the ground state configuration, electron-electron interactions, and hybridization between molecular orbitals. I will show the results of recently performed studies on plutonium oxide nanoparticles2–5, which were achieved by the combination of HERFD, RIXS, EXAFS, XRD, HEXS (PDF) synchrotron methods together with results on thorium6,7 and uranium8 oxide nanoparticles. The experimental results were analyzed using electronic structure calculations 9,10. It might be of interest for fundamental research in chemistry and physics of actinides as well as for applied science.