[K2(Bi@Pd12@Bi20)]4–: An Endohedral Inorganic Fullerene with Spherical Aromaticity

Inorganic fullerene clusters have attracted widespread attention due to their highly symmetrical geometric structures and intrinsic electronic properties. However, cage-like clusters composed of heavy metal elements with high symmetry are rarely reported, and their synthesis is also highly challenging. In this study, we present the synthesis of a [K