In a scientific advancement, researchers at the Department of Energy’s Oak Ridge National Laboratory (ORNL) have uncovered previously unknown properties of promethium, a rare earth element first identified at the same facility nearly 80 years ago. This discovery opens new frontiers in the exploration of critical elements that power technologies across industries, from medical applications to space exploration.

Legacy of Discovery

Promethium, discovered in 1945 at what was then known as Clinton Laboratories, has long remained an enigmatic member of the lanthanide series. Unlike its counterparts, promethium has no stable isotopes, making its study uniquely challenging. Despite its historical use in medical research and long-lived nuclear batteries, much about its chemical behavior remained unknown—until now.

A team led by ORNL scientists Alex Ivanov, Santa Jansone-Popova, and Ilja Popovs successfully characterized promethium in solution for the first time. Their landmark research, published in Nature, represents a significant step forward in rare earth chemistry and has the potential to reshape scientific understanding of lanthanide behavior.

Critical Elements

Using advanced laboratory resources, including research reactors, hot cells, and supercomputers, the team synthesized and purified promethium-147, an isotope with a half-life of 2.62 years. Through X-ray spectroscopy, they identified the properties of promethium’s chemical bonds—an achievement that fills a long-standing gap in the periodic table.

One of the most interesting findings was the demonstration of lanthanide contraction in solution, a phenomenon where elements in the lanthanide series exhibit decreasing ionic radii with increasing atomic numbers. The researchers found that this contraction accelerates up to promethium and then significantly slows down—a crucial insight into the structural and bonding properties of these elements.

The Implications

The ability to measure promethium’s chemical characteristics could seriously impact multiple industries. Rare earth elements, namely permanent magnets, are essential in modern technologies, used in wind turbines, electric vehicles, and consumer electronics. Additionally, the findings may streamline the complex process of separating lanthanides for industrial applications. Since many rare earth elements exist in mixtures, precise separation is essential for their effective use in high-tech manufacturing.

A Scientific Milestone

The ORNL team’s success was made possible through collaboration among experts in radiochemistry, spectroscopy, and computational chemistry. Leveraging facilities such as the High Flux Isotope Reactor and the Summit supercomputer, the researchers tackled one of the most challenging aspects of lanthanide science.

“This study adds the missing link to rare earth research,” said co-lead researcher Ilja Popovs. “Promethium was the last piece of the puzzle, and now we have a deeper understanding of its role in the periodic table.”

Apex Magnets

As the demand for rare earth elements grows, discoveries like this reinforce the importance of continued investment in scientific research. For businesses and researchers interested in harnessing the power of rare earth elements, these findings underscore the vast possibilities that lie ahead in materials science and engineering.

Contact Apex Magnets today if you’re interested in learning more about how magnets can make your business more efficient and cost effective.