In 1869, Russian chemist Dimitri Mendeleev wrote out the known elements (there were 63 at the time) on cards and arranged them in columns and rows according to their chemical and physical properties, introducing the concept of the Periodic Table. In celebration of the 150th anniversary of his work, the United Nations has declared 2019 the “Year of the Periodic Table.” UNESCO announced in their press release, “The Periodic Table of Chemical Elements is more than just a guide or catalogue of the entire known atoms in the universe; it is essentially a window on the universe, helping to expand our understanding of the world around us.”
UC Berkeley chemistry and physics faculty and alumni have long been involved in the discovery of new elements on the Table. Starting with Ernest Lawrence’s invention of the cyclotron in the 1930s, Berkeley and Lawrence Berkeley lab researchers, including Nobel Laureate Glenn Seaborg and nuclear scientist Albert Ghiorso (B.S. ’37, Elec. Engin.) were co-discovers of 16 elements between 1940 and 1974.
In 2016 it was announced by the International Union of Pure and Applied Chemistry (IUPAC) that four more elements were to be added to the table. The Heavy Element Group at Lawrence Livermore National Laboratory, currently led by alumna and nuclear chemist Dawn Shaughnessy (B.S. ’93; Ph.D. ’00, Nuclear Chem), worked with scientists at Vanderbilt University, Oak Ridge National Laboratory and in Russia and Japan on the newest elements’ discovery. The elements named nihonium, moscovium, tennessine, and oganesson have been given the atomic numbers 113, 115, 117, and 118.
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This story was updated June 3, 2019 to reflect a correction that Dr. Shaughnessy is the current director of the Heavy Element Group at LLNL and that scientists at Vanderbilt University and Oak Ridge National Laboratory were also integral to the discovery of the new elements.