New Progress Toward the Discovery of New Elements

Scientists are working to discover new elements and uncover the limits of the periodic table. This involves understanding how large an atom’s nucleus can become as it gains more protons and neutrons. It also involves identifying the heaviest element that could exist. Part of this search focuses on the idea of an “island of stability.” This is where extremely heavy elements might have special properties and last longer than expected. Recently, researchers created two atoms of livermorium (element 116) using a new approach that offers a path to discovering even heavier elements.

The Impact

This breakthrough brings scientists closer to creating a new element with 120 protons. Element 120 would be the heaviest element ever made. This would push the boundaries of the periodic table to a new eighth row and move closer to the “island of stability.” By exploring elements at the extremes, scientists are gaining new insights into how atoms work, the limits of atomic nuclei, and tests of theories on nuclear physics.

Summary

There are currently 118 known elements, 90 of which occur naturally on Earth. Elements heavier than fermium (which has 100 protons) must be created by combining the nuclei of two lighter elements, but not all combinations work. The heaviest, currently known elements were made by fusing a specific isotope of calcium, calcium-48 (with 20 protons and 28 neutrons), with heavier elements, but this method only works up to element 118 (oganesson). The special (so-called magic) numbers of protons and neutrons make the fusion of calcium and the survival of the resulting compound nucleus more likely. However, to go further, scientists need new techniques.

In a recent experiment, an international team of scientists led by Lawrence Berkeley National Laboratory’s Nuclear Science Division made a significant breakthrough by accelerating a beam of titanium-50 (with 22 protons and 28 neutrons) in the 88-Inch Cyclotron and fusing the titanium nuclei with nuclei from plutonium-244 (with 94 protons and 150 neutrons). Over the course of 22 days, the team successfully produced two atoms of the superheavy element livermorium. This experiment shows that new elements beyond oganesson can be created at Berkeley Lab. However, making element 120 is expected to be much harder— between 10 and 20 times more difficult than livermorium. If successful, element 120 would be the heaviest known element, providing new opportunities to explore the outermost limits of atomic structure and further test theories of nuclear physics.

Funding

This material is based on work supported by the Department of Energy Office of Science, Office of Nuclear Science; the Swedish Knut and Alice Wallenberg Foundation; the Wenner-Gren Foundations; the Cary Trygger Foundation; the Royal Physiographic Society in Lund; the Department of Energy Office of Science, Office of Basic Energy Sciences; the UK Science and Technology Facilities Council; a startup package from the Oregon State University College of Engineering; the Office of Nuclear Regulatory Research; the Nuclear Regulatory Commission; the Swiss National Science Foundation; and the French National Centre for Scientific Research.