Scientists have, for the first time, measured the bond distance of einsteinium, one of the most radioactive and difficult to make elements on the periodic table. Researchers detailed rare experiments on the element, which carries the atomic number 99, in a paper published Wednesday in the journal Nature. "[The finding] is 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," said UC Berkeley assistant professor of nuclear engineering and study author Rebecca Abergel.