Parasitism in Metal Nanoclusters: A Case Study of (AuAg)₂₅·(AuAg)₂₇

Studying the interactions of atomically precise metal nanoclusters in their assembly systems is of great significance in the nanomaterial research field, which has attracted increasing interest in the last few decades. Herein, we report the cocrystallization of two oppositely charged atomically precise metal nanoclusters in one unit cell: [Au 1 Ag 24 (SR) 18 ] – ((AuAg) 25 for short) and [Au x Ag 27– x (Dppf) 4 (SR) 9 ] 2+ ( x = 10–12; (AuAg) 27 for short) with a 1:1 ratio. (AuAg) 27 could maintain its structure in the presence of (AuAg) 25, whether in the crystalline and the solution state, while the metastable (AuAg) 27 component underwent a spontaneous transformation to (AuAg) 16 (Dppf) 2 (SR) 8 after dissociating the (AuAg) 25 component from this cocrystal, demonstrating the “parasitism” relationship of the (AuAg) 27 component over (AuAg) 25 in this dual-cluster system. This work enriches the family of cluster-based assemblies and elucidates the delicate relationship between nanoparticles of cocrystals.