Beyond The Sphere. Au(PR) as a Spherical Aromatic Cuboctahedron Cluster.

The icosahedral Au core is a recurrent building block in ligand-protected gold clusters involving an 8-cluster electron 1S1P electronic shell. Such a prototypical structure enables a spherical aromatic behavior as given by long-range magnetic shielding. Recently, the Au(BuP) cluster featuring a contrasting cuboctahedral core with formally neutral gold atoms appears as a novel core architecture with the potential to be considered as another potential building block towards functional nanostructures. Here, we explore the ligand-core interaction and spherical aromatic characteristics of Au(BuP), in order to provide a direct connection to classical icosahedral spherical aromatic compounds, now involving a cuboctahedral core structure. Such characteristics suggest rationalization of their robustness in terms of certain electron counts, enabling a shielding cone property in ligand-protected metallic clusters, which favors bridging organic and inorganic planar/spherical aromatic species towards the unification of the aromaticity concept and designing guidelines for further achievements.