Journal Article

Characterization of a strong covalent Th3+–Th3+ bond inside an Ih(7)-C80 fullerene cage

Rodríguez-Fortea, Antonio, Poblet, Josep M., Chen, Ning, Zhang, Jiangwei, Wang, Yaofeng, Yao, Yang-Rong, Pei, Cuiying, Zhuang, Jiaxin, Echegoyen, Luis, Morales-Martínez, Roser, Wang, Shuao, de Graaf, Coen

2021

Overview

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. Studying the nature of actinide-actinide bonds is important for understanding the electronic structure of the 5 f elements, but the synthesis of these chemical bonds remains extremely challenging. Here, the authors report a strong covalent Th-Th bond formed between two rarely accessible Th 3+ ions, stabilized inside a fullerene cage.

• Publisher: Nature Publishing Group UK,Nature Publishing Group
• Subject: 119/118 / 140/131 / 140/133 / 140/58 / 639/301/357/73 / 639/638/263/910 / Accessibility / Actinides / Bonding strength / Cages / Chemical bonds / Chemical synthesis / Covalence / Density functional theory / Electric arcs / Electronic structure / Fullerenes / Humanities and Social Sciences / Ions / Lymphocytes T / multidisciplinary / Quantum chemistry / Science / Science (multidisciplinary) / Single crystals / Thorium / X-ray diffraction