ORALS

Understanding of chemical behaviour of actinide elements is essential for the effective management and use of actinide materials. However, actinide structural chemistry is challenging from the perspectives of both experiments and theories. To date, some of the important actinide bonding motifs, such as actinide-actinide metal-metal bond and actinide multiple bond, can only be obtained in the unstable clusters in gas phase. The hollow internal cavity of fullerene buckyballs has been known to be able to encapsulate novel metallic units, especially those otherwise very reactive or virtually impossible to prepare clusters. In this talk, we will present our recent studies of novel actinide endohedral fullerenes, focusing on their unique bonding behaviors. We found that unprecedented actinide metal-metal bond and actinide-lanthanide metal-metal bond can be formed and stabilized inside a series of dimetallic metallofullerenes, such as U2@Ih(7)-C80 , Th2@Ih(7)-C80 and ThLn( Ln= Y, Dy)@Ih(7)-C2n. In addition, we obtained a series of stable molecule compounds which contains unique actinide bonds such as axial U=C bond and U≡C triple bond, enabling the experimental characterizations of these actinide bonds for the first time. These research results provide new perspective to the study of actinide bonds and endohedral fullerenes.