On the origin of low-valent uranium oxidation state.

Autor: Silva CL; The Rossendorf Beamline at ESRF-The European Synchrotron, CS40220, 38043, Grenoble Cedex, France.; Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Resource Ecology, 01314, Dresden, Germany., Amidani L; The Rossendorf Beamline at ESRF-The European Synchrotron, CS40220, 38043, Grenoble Cedex, France. lucia.amidani@esrf.fr.; Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Resource Ecology, 01314, Dresden, Germany. lucia.amidani@esrf.fr., Retegan M; European Synchrotron Radiation Facility (ESRF), CS40220, 38043, Grenoble Cedex, France., Weiss S; Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Resource Ecology, 01314, Dresden, Germany., Bazarkina EF; The Rossendorf Beamline at ESRF-The European Synchrotron, CS40220, 38043, Grenoble Cedex, France.; Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Resource Ecology, 01314, Dresden, Germany., Graubner T; Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Str. 4, 35032, Marburg, Germany., Kraus F; Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Str. 4, 35032, Marburg, Germany., Kvashnina KO; The Rossendorf Beamline at ESRF-The European Synchrotron, CS40220, 38043, Grenoble Cedex, France. kristina.kvashnina@esrf.fr.; Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Resource Ecology, 01314, Dresden, Germany. kristina.kvashnina@esrf.fr.
Jazyk: angličtina
Zdroj: Nature communications [Nat Commun] 2024 Aug 10; Vol. 15 (1), pp. 6861. Date of Electronic Publication: 2024 Aug 10.
DOI: 10.1038/s41467-024-50924-7
Abstrakt: The significant interest in actinide bonding has recently focused on novel compounds with exotic oxidation states. However, the difficulty in obtaining relevant high-quality experimental data, particularly for low-valent actinide compounds, prevents a deeper understanding of 5f systems. Here we show X-ray absorption near-edge structure (XANES) measurements in the high-energy resolution fluorescence detection (HERFD) mode at the uranium M 4 edge for the U III and U IV halides, namely UX 3 and UX 4 (X = F, Cl, Br, I). The spectral shapes of these two series exhibit clear differences, which we explain using electronic structure calculations of the 3d-4f resonant inelastic X-ray scattering (RIXS) process. To understand the changes observed, we implemented crystal field models with ab initio derived parameters and investigated the effect of reducing different contributions to the electron-electron interactions involved in the RIXS process. Our analysis shows that the electron-electron interactions weaken as the ligand changes from I to F, indicative of a decrease in ionicity both along and between the UX 3 and UX 4 halide series.
(© 2024. The Author(s).)
Databáze: MEDLINE