Core Charge Density Dominated Size‐Conversion from Au6P8 to Au8P8Cl2. Issue 54 (2nd September 2020) - Lv, Ying
Abstract: The stimulus‐response of metal nanoclusters is crucial to their applications in catalysis and bio‐clinics, etc. However, its mechanistic origin has not been well studied. Herein, the mechanism of the Au I PPh3 Cl‐induced size‐conversion from [Au6 (DPPP)4 ] 2+ to [Au8 (DPPP)4 Cl2 ] 2+ (DPPP is short for 1, 3‐bis(diphenylphosphino)propane) is theoretically investigated with density functional theory (DFT) calculations. The optimal size‐growth pathway, and the key structural parameters were elucidated. The Au−P bond dissociation steps are key to the size‐growth, the easiness of which was determined by the charge density of the metallic core of the cluster precursors (i.e., "core charge density"). This study sheds light on the inherent structure–reactivity relationships during the size‐conversion, and will benefit the deep understanding on the kinetics of more complex systems. Abstract : Down to the core : The mechanism of Au I ‐induced conversion of Au6 P8 to Au8 P8 Cl2 was elucidated by DFT calculations. The Au−P bond cleavage steps dominate the facility of the size‐conversion, and its easiness is determined by the core charge density: the higher core charge, the easier Au−P dissociation. In addition, the quasi‐metallic character of chloride induces its extremely easy migration around the metal core to generate the thermodynamic product.