Synthesis of atomically precise silver clusters by using the miscibility principle

A new strategy to synthesize a diverse array of organic-soluble, atomically precise silver clusters has been developed. The technique is based on the miscibility principle of solvents and uses no phase-transfer agents; various clusters of masses 8.0, 13.4, 22.8, 29.2, and 34.4 kDa were synthesized by changing the reactant composition. We have also synthesized the well-known Au25(SR)18 cluster by the same method. Among the silver clusters formed, we have studied the new 13.4 kDa species, which has unique steplike features in its UV/Vis spectrum, in detail by mass spectrometry and other analytical techniques. The compound has been assigned as Ag68(SR)34, which is reported for the first time. By time-dependent studies, we have shown that the synthetic route follows the bottom-up approach. The material forms microcrystals. We hope that the proposed synthetic strategy will extend the area of atomically precise clusters.