Insight Into the Stability and Electronic and Optical Properties of N-Heterocyclic Carbene Analogues of Halogen/Phosphine-Protected Au-13 Superatomic Clusters

Atomically precise gold nanoclusters (AuNCs) belong to a relevant area oflering useful templates with tunable properties toward functional nanostructures. In this work, we explored the feasible incorporation of N-heterocyclic carbenes (NHCs), as part of the protecting-ligand shell in AuNCs. Our results, which are based on the substitution of phosphine ligands in experimentally characterized AuNCs by NHCs in various eight-electron superatoms Au-13 and M4Au9 (M = Cu, Ag), indicate similar electronic structure and stability but somewhat diflerent optical properties. These findings support the feasible obtention of novel targets for explorative synthetic eflorts featuring NHC ligands on medium-sized species based on the recurrent Au-13 icosahedral core. The hypothetical species appear to be interesting templates for building blocks in nanostructured materials with tuned properties, which encourage experimental exploration of ligand versatility in homo-and heterometallic superatomic clusters.