First-ever measurements unlock hidden properties of neptunium oxide

Los Alamos material scientists collaborated to perform the first detailed experimental characterization of neptunium pentoxide (Np2O5), a little-studied actinide material important for nuclear science and national security applications. The paper was published in Nature Scientific Reports and led by Savannah River National Laboratory.
 
Read the paper
 
Why this matters: The study demonstrates how advanced spectroscopy and modeling can reveal the electronic and structural behavior of complex radioactive materials. The approach could support future advances in nuclear fuel processing, waste storage and actinide science.
 
What the team did and what they discovered:

• The team conducted the first Raman spectroscopy on single crystal Np2O5 and the first scanning tunneling spectroscopy experiments reported for a neptunium-containing material. They combined experiments with density functional theory calculations to interpret the results.
• Researchers measured an electronic band gap of approximately 1.5 electron volts and identified previously unknown vibrational modes that reveal how atoms move and interact within the crystal structure.
• The study demonstrates how combining advanced spectroscopy, crystal growth and predictive modeling can reveal fundamental properties of challenging actinide systems and improve confidence in simulations used for nuclear science and stockpile readiness applications.

Funding: The work at Los Alamos was supported by the U.S. Department of Energy's Office of Science, Office of Basic Energy Sciences, Heavy Element Chemistry program and the Laboratory’s G.T. Seaborg Institute for Transactinium Science. 

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