Pseudotetrahedral Organotin-Capped Chalcogenidometalate Supermolecules with Optical Limiting Performance.

The rational design of crystalline clusters with adjustable compositions and dimensions is highly sought after but quite challenging as it is important to understand their structural evolution processes and to systematically establish structure-property relationships. Herein, a family of organotin-based sulfidometalate supertetrahedral clusters has been prepared via mixed metal and organotin strategies at low temperatures (60-120 °C). By engineering the metal composition, we can effectively control the size of the clusters, which ranges from 8 to 35, accompanied by variable configurations: P1-[(RSn) 4 M 4 S 13 ], T3-[(RSn) 4 In 4 M 2 S 16 ] (R = n butyl-Bu and phenyl-Ph; M = Cd, Zn, and Mn), T4-[(BuSn) 4 In 13 Cu 3 S 31 ], truncated P2, viz. TP2-[(BuSn) 6 In 10 Cu 6 S 31 ], and even T5-[(BuSn) 4 In 22 Zn 6 Cu 3 S 52 ], all of which are the largest organometallic supertetrahedral clusters known to date. Of note, the arylstannane approach plays a critical role in regulating the peripheral ligands and further enriching geometric structures of the supertetrahedral clusters. This is demonstrated by the formation of tin-oxysulfide clusters, such as T3-[(RSn) 4 Sn 6 O 4 S 16 ] (R = Bu, Ph, and benzyl = Be) and its variants, truncated T3, viz., TT3-[(BuSn) 6 Sn 3 O 4 S 13 ] and augmented T3, viz., T3-[(Bu 3 SnS) 4 Sn 6 O 4 S 16 ]. Especially, two extraordinary truncated clusters break the tetrahedral symmetry observed in typical supertetrahedral clusters, further substantiating the advantages offered by the arylstannane approach in expanding cluster chemistry. These organometallic supertetrahedral clusters are highly soluble and stable in common solvents. Additionally, they have tunable third-order nonlinear optical behaviors by controlling the size, heterometallic combination, organic modification, and intercluster interaction.