Tri- and Tetra-superatomic Molecules in Ligand-Protected Face-Fused Icosahedral (M@Au-12)(n) (M = Au, Pt, Ir, and Os, and n=3 and 4) Clusters

Cluster assembling has been one of the hottest topics in nanochemistry. In certain ligand- protected gold clusters, bi-icosahedral cores assembled from Au-13 superatoms were found to be analogues of diatomic molecules F-2, N-2, and singlet O-2, respectively, in electronic shells, depending upon the super valence bond (SVB) model. However, challenges still remain for extending the scale in cluster assembling via the SVB model. In this work, ligand-protected tri- and tetra-superatomic clusters composed of icosahedral M@Au-12 (M = Au, Pt, Ir, and Os) units are theoretically predicted. These clusters are stable with reasonable highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) energy gaps and proven to be analogues of simple triatomic (Cl-3(-), OCl2, O-3, and CO2) and tetra-atomic (N C-C N, and Cl-C C-Cl) molecules in both geometric and electronic structures. Moreover, a stable cluster-assembling gold nanowire is predicted following the same rules. This work provides effective electronic rules for cluster assembling on a larger scale and gives references for their experimental synthesis.