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DOE OSTI · 1835698

Direct measurement of 5f delocalization with U XES

Tobin, J. G.·Nowak, S.·Yu, S. -W.·Alonso-Mori, R.·Kroll, T.·Nordlund, D.·Weng, T. -C.·Sokaras, D.
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Abstract

Delocalization of the 5f states in the early actinides in general and U metal in particular is significantly important and yet poorly understood. Here, extant spectroscopic techniques have failed to resolve the situation. Here it will be shown that X-Ray Emission Spectroscopy (XES) of the M 4,5 levels can provide the needed information, with a distinct difference between the delocalized U metal and localized uranium dioxide and uranium tetrafluoride cases. A Peak Ratio (PR) model, built upon electric dipole selection rules, has been developed and utilized, with quantitative agreement between experiment and theory. Possible expansion to other types of 5f mixing systems will be discussed.

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36 MATERIALS SCIENCEU, x-ray fluorescenceactinideelectronic structurespectroscopy

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Tobin, J. G., Nowak, S., Yu, S. -W., Alonso-Mori, R., Kroll, T., Nordlund, D., Weng, T. -C., Sokaras, D.. 2022-10-31. Direct measurement of 5f delocalization with U XES. https://doi.org/10.1557/s43577-022-00419-x

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36 MATERIALS SCIENCE↗