Application of High-Energy-Resolution X-ray Absorption Spectroscopy at the U L3-Edge to Assess the U(V) Electronic Structure in FeUO4

Takumi Yomogida; Daisuke Akiyama; Kazuki Ouchi; Yuta Kumagai; Kotaro Higashi; Yoshihiro Kitatsuji; Akira Kirishima; Naomi Kawamura; Yoshio Takahashi

doi:10.1021/acs.inorgchem.2c03208

Application of High-Energy-Resolution X-ray Absorption Spectroscopy at the U L₃-Edge to Assess the U(V) Electronic Structure in FeUO₄

Inorg Chem. 2022 Dec 19;61(50):20206-20210. doi: 10.1021/acs.inorgchem.2c03208. Epub 2022 Dec 2.

Authors

Takumi Yomogida^{1

2}, Daisuke Akiyama³, Kazuki Ouchi², Yuta Kumagai², Kotaro Higashi⁴, Yoshihiro Kitatsuji², Akira Kirishima³, Naomi Kawamura⁴, Yoshio Takahashi^{1

5

6}

Affiliations

¹ Department of Earth and Planetary Science, The University of Tokyo, Hongo 7-3-1, Bunkyo, Tokyo 113-0033, Japan.
² Nuclear Science and Engineering Center, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195, Japan.
³ Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 1-1 Katahira 2, Aoba, Sendai, Miyagi 980-8577, Japan.
⁴ Center for Synchrotron Radiation Research, Japan Synchrotron Radiation Research Institute (JASRI), Sayo, Hyogo 679-5198, Japan.
⁵ Isotope Science Center, University of Tokyo, Bunkyo, Tokyo 113-0032, Japan.
⁶ Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization, KEK, Tsukuba, Ibaraki 305-0801, Japan.

Abstract

FeUO₄ was studied to clarify the electronic structure of U(V) in a metal monouranate compound. We obtained the peak splitting of spectra utilizing high-energy-resolution fluorescence detection-X-ray absorption near-edge structure (HERFD-XANES) spectroscopy at the U L₃-edge, which is a novel technique in uranium(V) monouranate compounds. Theoretical calculations revealed that the peak splitting was caused by splitting of the 6d orbital of U(V) in FeUO₄, which would be used to detect minor U(V) species. Such distinctive electronic states are of major interest to researchers and engineers working in various fields, from fundamental physics to the nuclear industry and environmental sciences for actinide elements.