Core-Modulation of 70-nuclei Core-Shell Silver Nanoclusters.

The reaction of {(HNEt3)2[Ag10(tBuC6H4S)12]}n, Ag2O, Na2MoO4 and m-methoxybenzoic acid (Hmbc) in CH3OH/CH2Cl2 led to only yellow crystals of [Ag4S4(MoO4)5@Ag66] (SD/Ag70b; SD = SunDi), but in the presence of DMF additional dark-red crystals of [Ag10@(MoO4)7@Ag60] (SD/Ag70a) were obtained. The former consists of five MoO42- wrapped by a shell of 66 Ag atoms. The latter contains a rare Ag10 kernel consisting of five tetrahedra sharing faces and edges ringed by seven MoO42- which is enclosed in a shell of 60 Ag atoms. The formation of the Ag10 kernel is originated from reduction reaction involving DMF during the self-assembly process. This work not only provides the important structural information (fused five Ag4 tetrahedra) for a unique Ag10 kernel but also paves an avenue to trap elusive silver species by hierarchical multi-shell silver nanocluster assembly with the help of anion templates.