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arXiv · 1002.0240

5d-5f Electric-multipole Transitions in Uranium Dioxide Probed by Non-resonant Inelastic X-ray Scattering

R. Caciuffo·G. van der Laan·L. Simonelli·T. Vitova·C. Mazzoli·M. A. Denecke·G. H. Lander
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Abstract

Non-resonant inelastic x ray scattering (NIXS) experiments have been performed to probe the 5d-5f electronic transitions at the uranium O(4,5) absorption edges in uranium dioxide. For small values of the scattering vector q, the spectra are dominated by dipole-allowed transitions encapsulated within the giant resonance, whereas for higher values of q the multipolar transitions of rank 3 and 5 give rise to strong and well-defined multiplet structure in the pre-edge region. The origin of the observed non-dipole multiplet structures is explained on the basis of many-electron atomic spectral calculations. The results obtained demonstrate the high potential of NIXS as a bulk-sensitive technique for the characterization of the electronic properties of actinide materials.

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R. Caciuffo, G. van der Laan, L. Simonelli, T. Vitova, C. Mazzoli, M. A. Denecke, G. H. Lander. 2010-02-01. 5d-5f Electric-multipole Transitions in Uranium Dioxide Probed by Non-resonant Inelastic X-ray Scattering. https://doi.org/10.1103/physrevb.81.195104

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