Einsteinium is a heavy, trivalent actinide element found in the actinide series at the bottom of the periodic table. Like all of the other actinides, it has a stable oxidation state of +3 in both solids and aqueous solutions.
It also has a unique chemical property called the bond length that differs greatly from the rest of its family. This has been experimentally confirmed for the first time in the actinide series, a new study published today in the Journal of Chemical Physics reports.
The bond length is a key property that explains how an element will react with other elements. Carter and her colleagues used a spectrometer to measure the average distance between two atoms bonded together in a sample of the element. They found that the einsteinium bond length is significantly shorter than that of other actinide elements, which they say is a surprising discovery.
They also measured the atomic ionization energies of the element, which they discovered are quite high, but not as high as those of its heavier brother, californium. This is an important finding for understanding how the two actinides will interact in a chemical reaction, and may help researchers predict how they will behave when they are combined with other elements.
One of the few transuranic elements that scientists know little about, number 99 – einsteinium – has long been elusive due to its extreme radioactivity and difficulty in making. However, a team of researchers from Berkeley Lab has overcome these challenges to report the first study characterizing some of its properties, opening up a new door for studying the remaining transuranic elements in the actinide series.