Abstract
Raman spectra of three NpO2 samples and two samples produced from a modified direct denitration (MDD) process were collected. The spectral features of the NpO2 samples were consistent and indicated only NpO2. The spectra of the MDD samples indicated the presence of NpO2 and an additional phase attributed to the neptunium binary oxide Np2O5. These Raman spectra are the first reported of Np2O5, and the proportions of these neptunium oxide phases varied within the samples, suggesting significant sample inhomogeneity. Peaks in the Raman spectra of Np2O5 at 569 and 782 cm−1 were tentatively assigned to concerted, symmetric stretches of the neptunyl cations. Laser-induced heating of regions in the MDD samples that were rich in Np2O5 showed spectral features that indicated conversion to NpO2.
| Original language | English |
|---|---|
| Article number | 124954 |
| Journal | Journal of Solid State Chemistry |
| Volume | 339 |
| DOIs | |
| State | Published - Nov 2024 |
Funding
Notice: This manuscript has been authored by UT-Battelle, LLC, under contract DE-AC05-00OR22725 with the US Department of Energy (DOE). The US government retains and the publisher, by accepting the article for publication, acknowledges that the US government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for US government purposes. DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (https://www.energy.gov/doe-public-access-plan).Funding for this research was provided by the Science Mission Directorate of NASA and administered by the US Department of Energy, Office of Nuclear Energy, under contract DEAC05-00OR22725. SEG would like to acknowledge the Glenn T. Seaborg Institute for support. This work utilized the facilities and resources at the Radiochemical Engineering Development Center operated by the US Department of Energy's Oak Ridge National Laboratory.The authors thank Kaara Patton for assistance with obtaining neptunium oxide samples. S.E.G. wishes to thank Samantha Schrell for insightful scientific conversations. This work was supported by the 238Pu Supply Program at Oak Ridge National Laboratory. Funding for this research was provided by the Science Mission Directorate of NASA and administered by the US Department of Energy, Office of Nuclear Energy, under contract DEAC05-00OR22725. SEG would like to acknowledge the Glenn T. Seaborg Institute for support. This work utilized the facilities and resources at the Radiochemical Engineering Development Center operated by the US Department of Energy\u2019s Oak Ridge National Laboratory.
| Funders | Funder number |
|---|---|
| National Aeronautics and Space Administration | |
| DOE Public Access Plan | |
| Oak Ridge National Laboratory | |
| U.S. Department of Energy | |
| Glenn T. Seaborg Institute | |
| Office of Nuclear Energy | DEAC05-00OR22725 |
Keywords
- Actinyl-actinyl interactions
- Cation-cation interactions
- Neptunium oxide
- NpO
- Raman spectroscopy