Actinide Science

Only the members of the actinide group through plutonium, or Pu, occur in nature. Thorium and uranium occur widely in the earth’s crust in combination with other elements, and, in the case of uranium, in significant concentrations in the oceans. But the other actinide elements are synthetic in origin − products of nuclear reactions.

Actinide science encompasses many areas across ORNL, including national security, materials science, medical isotopes, radiochemistry and nuclear chemistry − making the national lab a natural fit for a Seaborg Institute. All the actinide elements are radioactive, and, except for thorium and uranium, must be handled with special equipment and shielded facilities like the ones at ORNL.

Actinides, which release energy as they decay, are being used in cancer-fighting therapies and as self-contained sources of electricity. They power devices as varied as cardiac pacemakers in the body, nuclear power plants, smoke detectors and instruments used to gather information on deep-space missions to other planets and moons.

“Actinides act like no other elements in the periodic table,” said Sam Schrell, director of ORNL’s Glenn T. Seaborg Institute. “A lot of their chemistry is complex, which is why scientists and engineers are so fascinated by it. It’s not normal — it’s a challenge.”

That’s why Seaborg institutes are more than just workforce initiatives, she said. They’re incubators for ground-breaking discoveries.

“Much of actinide science is still a mystery,” she said. “We want to play a part in being able to explain it someday.”