Loading single lanthanide ion into aluminum molecular rings: water-stable sodalite cage for removal of nuclear-industry anions

Based on our discovery of neutral aluminum molecular rings, we herein introduce rare earth ions into the center of the ring and reveal their structural adaptability. The resulting yoyo-like cationic macrocycles are highly adaptive to guests, creating unusual supramolecular assemblies. The first category is stacked with singly oriented rhombohedral channels, which exhibit fast and reversible solvent-triggered molecular motions and structural rearrangements The second type of assembly is that yoyo macrocycles and guest molecules form a nested host-guest sodalite cage supramolecular structure. It is uncommon for guest molecules to be well-defined within cages although caged structures have been well-documented Their host-guest interaction discussion reveals the self-adaptation and flexibility of the yoyo macrocycles. Considering their good water stability, we investigated their anion exchange properties. The results show that they have significant exchange capacity for KI/I 2 , \({\rm{Re}}{{\rm{O}}_4}^ - \) , and \({\rm{Mn}}{{\rm{O}}_4}^ - \) , revealing their potential application in water purification and nuclear waste treatment.