Researchers at Los Alamos provided critical assistance in this step by designing a sample holder uniquely suited to the challenges intrinsic to einsteinium. So they had to scrap their original plan to use X-ray crystallography-which is considered the gold standard for obtaining structural information on highly radioactive molecules but requires a pure sample of metal-and instead came up with a new way to make samples and leverage element-specific research techniques. The first problem they encountered was that the sample was contaminated with a significant amount of californium, as making pure einsteinium in a usable quantity is extraordinarily challenging. The material was made at Oak Ridge National Laboratory's High Flux Isotope Reactor, one of only a few places in the world that is capable of making einsteinium, which involves bombarding curium targets with neutrons to trigger a long chain of nuclear reactions.
#The periodic table chemistry next step inquiry series
"This whole paper is a long series of unfortunate events," she said wryly. And we can establish trends in the periodic table."Ībergel and her team used experimental facilities not available decades ago when einsteinium was first discovered-the Molecular Foundry at Berkeley Lab and the Stanford Synchrotron Radiation Lightsource (SSRL) at SLAC National Accelerator Laboratory, both DOE Office of Science user facilities-to conduct luminescence spectroscopy and X-ray absorption spectroscopy experiments.īut first, getting the sample in a usable form was almost half the battle. It's significant because the more we understand about its chemical behavior, the more we can apply this understanding for the development of new materials or new technologies, not necessarily just with einsteinium, but with the rest of the actinides too. "It's a remarkable achievement that we were able to work with this small amount of material and do inorganic chemistry.
"There's not much known about einsteinium," said Abergel, who leads Berkeley Lab's Heavy Element Chemistry group and is an assistant professor in UC Berkeley's Nuclear Engineering department. With less than 250 nanograms of the element, the team measured the first-ever einsteinium bond distance, a basic property of an element's interactions with other atoms and molecules. Published in the journal Nature, the study, "Structural and Spectroscopic Characterization of an Einsteinium Complex," was co-led by Berkeley Lab scientist Rebecca Abergel and Los Alamos National Laboratory scientist Stosh Kozimor, and included scientists from the two laboratories, UC Berkeley, and Georgetown University, several of whom are graduate students and postdoctoral fellows.
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