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arXiv · 0809.3843

X-ray absorption branching ratio in actinides: LDA+DMFT approach

J. H. Shim·K. Haule·G. Kotliar
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Abstract

To investigate the x-ray absorption (XAS) branching ratio from the core 4d to valence 5f states, we set up a theoretical framework by using a combination of density functional theory in the local density approximation and Dynamical Mean Field Theory (LDA+DMFT), and apply it to several actinides. The results of the LDA+DMFT reduces to the band limit for itinerant systems and to the atomic limit for localized f electrons, meaning a spectrum of 5f itinerancy can be investigated. Our results provides a consistent and unified view of the XAS branching ratio for all elemental actinides, and is in good overall agreement with experiments.

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J. H. Shim, K. Haule, G. Kotliar. 2008-09-23. X-ray absorption branching ratio in actinides: LDA+DMFT approach. https://doi.org/10.1209/0295-5075/85/17007

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