Unraveling 5f-6d hybridization in uranium compounds via spin-resolved L-edge spectroscopy

• Published in: Nature communications Vol. 8; no. 1; pp. 1203 - 6
• Main Authors: dos Reis, R. D., Veiga, L. S. I., Escanhoela Jr, C. A., Lang, J. C., Joly, Y., Gandra, F. G., Haskel, D., Souza-Neto, N. M.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 31.10.2017; Nature Publishing Group; Nature Portfolio
• Subjects: 639/301/930; 639/766/119/997; 639/766/36/1122; Absorption cross sections; Actinide compounds; ATOMIC AND MOLECULAR PHYSICS; Circular dichroism; Condensed Matter; Conduction; Dichroism; Electron states; Electronic structure; Humanities and Social Sciences; Hybridization; Magnetism; Materials Science; multidisciplinary; Physics; Science; Science (multidisciplinary); Spectroscopy; Uranium compounds
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-017-01524-1

The multifaceted character of 5 f electrons in actinide materials, from localized to itinerant and in between, together with their complex interactions with 6 d and other conduction electron states, has thwarted efforts for fully understanding this class of compounds. While theoretical efforts abound, direct experimental probes of relevant electronic states and their hybridization are limited. Here we exploit the presence of sizable quadrupolar and dipolar contributions in the uranium L 3 -edge X-ray absorption cross section to provide unique information on the extent of spin-polarized hybridization between 5 f and 6 d electronic states by means of X-ray magnetic circular dichroism. As a result, we show how this 5 f -6 d hybridization regulates the magnetism of each sublattice in UCu 2 Si 2 and UMn 2 Si 2 compounds, demonstrating the potentiality of this methodology to investigate a plethora of magnetic actinide compounds. Study and identification of the actinide electronic structure is complicated and crucial. Here the authors probe the hybridization between 5 f to 6 d orbitals in uranium compounds using X-ray magnetic circular dichroism near U-L3 edge through the dipolar and quadrupolar spectral contributions.