"the first structural characterization of a Pu–C bond. Absorption spectroscopy and DFT calculations indicate that the Pu2+ ion has predominantly a 5f6 electron configuration with some 6d mixing."
I really appreciate the team's effort to try to fully characterize the compounds here. Think about it, there is some real radioactivity concern first of all. Secondly, since the plutonium is weapons-grade, I am pretty sure there is a lot of concern about material being lost/wasted etc. Nevertheless, they managed to collect the characterization data that is necessary. In addition to the data, they also provided some photos of the compounds and the crystals which I think are really cool. You don't see plutonium compounds often. What I really liked though is the explanation (which I totally agree) they provided for the solvent impurities in the NMR samples. From the SI:
"Solvent impurities in the deuterated solvents in this spectrum and others are difficult to eliminate because a negative pressure glovebox , operated for safe containment of transuranic α - particle emitting radioisotopes , cannot have the atmosphere purged for safety reasons (pressure inside the box must remain negative relative to the laboratory atmosphere at all times ). Once discovered by NMR , it would take several weeks of work to repeat the plutonium experiments and attempt to remove all traces of solvent impurities (which may not be successful) . Since these impurities do not change the results or conclusions , the aesthetic improvement that might be gained from the extensive work required was not pursued."
Overall, great work I think!