Unravelling the reactions between a hydride-protected Ag18 nanocluster and thiol by the crystallization of intermediates

Abstract

Despite the significant progress accomplished in the synthesis and characterization of atomically precise noble metal nanoclusters (APCs) through ligand exchange-induced structural transformation (LEIST), an in-depth understanding of the chemistry remains elusive. Herein, we report a study of the transformation of [Ag18H16(TPP)10]2+ (where H- and TPP are hydride and triphenyl phosphine ligands, respectively) to smaller molecular entities upon ligand exchange with TFMBT-H (acronym for 2,3,5,6-tetrafluoro-4-(trifluoromethyl) benzenethiol) at different stoichiometric ratios, and investigate the reaction pathways using experimental and computational approaches. Different products, namely, [Ag(TFMBT)(TPP)3], [Ag6(TFMBT)6(TPP)6] and [Ag7(TFMBT)8(TPP)9], were formed depending on the cluster to thiol ratio. The study shows that, the composition provides a valuable handle for isolating and characterizing the intermediates involved in the ligand exchange process of clusters.