N-Heterocyclic Thione-Protected Ag4 Tetrahedra and Ag8 Cubes Cocrystallized in a Single Crystal

Polynuclear silver clusters have attracted intensive attention in the academic community owing to their rich physicochemical properties. The development of thione-protected silver clusters has been lagging behind the well-explored thiolate-protected silver-sulfide clusters. Herein, we report two N-heterocyclic thione-protected silver clusters: [Ag-4(2-TBI)(6)(SO4)(3)](2-)(Ag-4) and [Br@Ag-8(2-TBI)(12)(SO4)(2)](3+) (Ag-8) (2-TBI = 2-thiobenzimidazol), which cocrystallize to form clusterbased molecular crystals with a CaF2-type structure. The cocrystal shows high thermal stability in air. Notably, the two cluster-based layers are alternately assembled to exhibit a unique k-vectordifferential crystallographic arrangement. This work may lay a foundation for synthesis of atomically precise and stable silver clusters using readily available N-heterocyclic thione ligands.

Automated summary

In this study, two novel N-heterocyclic thione-protected silver clusters were reported, which could form cluster-based molecular crystals with high thermal stability. This work lays a foundation for the synthesis of atomically precise and stable silver clusters using readily available N-heterocyclic thione ligands.