ALD21: Clarice Phelps, Nuclear Chemist

Clarice Phelps

Clarice Phelps is a nuclear chemist who was part of the Oak Ridge National Laboratory (ORNL) team that worked with the Joint Institute for Nuclear Research to discover tennessine (element 117). She is the first African-American woman to have contributed to the discovery of a chemical element. 

Tennessine, a synthetic superheavy element, is the second heaviest element in the periodic table. Phelps was part of the ORNL team that purified the berkelium-249 which would be fused with calcium-48 in a high-energy particle accelerator in Russia to create tennessine. 

“We spent months pouring over calculations, preparing reagents, putting items in the glove box, going over everything over and over and over again,” Phelps told The Brilliant

Berkelium-249 has a half-life of 330 days, but the sample needed to be used within six months for the experiment to work. Despite Russian officials rejecting the package twice due to incomplete paperwork, the berkelium-249 eventually made it to Russia in June 2009. The discovery of tennessine was announced in April 2010 and officially recognised in 2015. 

Phelps is now the program manager for the Ni-63 and Se-75 industrial use isotope programs at ORNL, and is working on methods for separating actinide and lanthanide isotopes for medical use.

You can follow her work here:

Twitter: @ClaricePhelps39.

Further reading

Posted in Ada Lovelace Day 2021.