The periodic table rang in 2016 with a newly completed seventh row, after the International Union of Pure & Applied Chemistry formally recognized the discoveries of elements 113, 115, 117, and 118. A few weeks ago, the elements got their final names: nihonium, moscovium, tennessine, and oganesson, respectively.
European-American collaborations involving Russia’s Joint Institute for Nuclear Research and the U.S. Lawrence Livermore and Oak Ridge national laboratories named the other three elements. Moscovium (Mc) and tennessine (Ts) recognize the Moscow and Tennessee areas, respectively. Oganesson (Og) honors Russian nuclear physicist Yuri T. Oganessian, who leads the Flerov Laboratory of Nuclear Reactions at the Joint Institute for Nuclear Research.
What fascinates researchers about superheavy elements in the seventh row and beyond is their potential chemistry, says Dawn Shaughnessy, leader of the nuclear and radiochemistry group at Lawrence Livermore National Laboratory. As the number of protons in an atomic nucleus increases, electrons speed up and generate relativistic effects that alter orbital energy levels. That could mean that group reactivity trends don’t hold as elements get heavier. But to find out if that happens, chemists must first determine how to study the short-lived atoms, which are created one at a time in heavy-ion accelerators.