Synthesis and properties of an Au₆ cluster supported by a mixed N-heterocyclic carbene–thiolate ligand

Abstract

The preparation of a novel Au₆ cluster bearing a bidentate mixed carbene-thiolate ligand is presented. The length of linker between the central benzimidazole and thiolate has a strong effect on the formation of cluster products, with a C₂ chain giving an Au₆ cluster, while a C₃ chain results in no evidence of cluster formation. Density functional theory analysis predicts a non-metallic cluster with a large HOMO-LUMO (3.2-3.6 eV) and optical gap.