Deciphering synergetic core-shell transformation from [MoO@Ag] to [MoO@Ag].

The structural transformation of high-nuclearity silver clusters from one to another induced by specific stimuli is of scientific significance in terms of both cluster synthesis and reactivity. Herein, we report two silver-thiolate clusters, [MoO@Ag] and [MoO@Ag], which are templated by isopolymolybdates inside and covered by PrS and PhCOO ligands on the surfaces. Amazingly, the [MoO@Ag] can be transformed from [MoO@Ag] by adding PhCOOH which increases the degree of condensation of molybdates template from MoO to MoO, then enlarging the outer silver shell from Ag to Ag. The evolution of solution species revealed by time-dependent electrospray ionization mass spectrometry (ESI-MS) suggests a breakage-growth-reassembly (BGR) transformation mechanism. These results not only provide a combined assembly strategy (anion-template + induced transformation) for the synthesis of silver-thiolate clusters but also help us to better understand the complex transformation process underpinning the assembly system.