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Title: Characterization of a strong covalent Th3+–Th3+ bond inside an Ih(7)-C80 fullerene cage
Abstract The nature of the actinide-actinide bonds is of fundamental importance to understand the electronic structure of the 5 f elements. It has attracted considerable theoretical attention, but little is known experimentally as the synthesis of these chemical bonds remains extremely challenging. Herein, we report a strong covalent Th-Th bond formed between two rarely accessible Th 3+ ions, stabilized inside a fullerene cage nanocontainer as Th 2 @ I h (7)-C 80 . This compound is synthesized using the arc-discharge method and fully characterized using several techniques. The single-crystal X-Ray diffraction analysis determines that the two Th atoms are separated by 3.816 Å. Both experimental and quantum-chemical results show that the two Th atoms have formal charges of +3 and confirm the presence of a strong covalent Th-Th bond inside I h (7)-C 80 . Moreover, density functional theory and ab initio multireference calculations suggest that the overlap between the 7 s /6 d hybrid thorium orbitals is so large that the bond still exists at Th-Th separations larger than 6 Å. This work demonstrates the authenticity of covalent actinide metal-metal bonds in a stable compound and deepens our fundamental understanding of f element metal bonds.  more » « less
Award ID(s):
1801317
PAR ID:
10274693
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Nature Communications
Volume:
12
Issue:
1
ISSN:
2041-1723
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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