Berkelium-249, contained in the greenish fluid in the tip of the vial, was crucial to the experiment that discovered element 117. It was made in the research reactor at the U.S. Department of Energy’s Oak Ridge National Laboratory. (Photo by ORNL)

Twenty-two milligrams of a very pure synthetic material produced at Oak Ridge National Laboratory were used in the discovery of two new chemical elements that will help fill out the seventh row of the periodic table.

The synthetic element, berkelium-249, was produced in a project that started with a six-month irradiation of a target material at the High Flux Isotope Reactor at ORNL. The resulting product was separated and processed during a three-month period at the lab’s Radiochemical Engineering Development Center.

The berkelium-249 was then shipped to the Joint Institute for Nuclear Research, or JINR, in Dubna, Russia, where it was intensely bombarded, or irradiated, with calcium-48 ions, creating six atoms of element 117, said Jim Roberto, ORNL associate lab director for science and technology partnerships. Berkelium-249, which does not exist in nature, has a 300-day lifetime, so researchers had a short time to do their experiments.

Element 117 is one of four new elements that have been officially verified by the International Union for Pure and Applied Chemistry. The IUPAC announced the discoveries on December 30. The other three are elements 113, 115, and 118. Element 115 is produced when element 117 decays. [Read more…]