Synthesis of Trimetallic (HPd@M(2)Au(8))(3+) Superatoms (M = Ag, Cu) via Hydride-Mediated Regioselective Doping to (Pd@Au(8))(2+)

[Image: see text] We have recently reported that hydride (H(–)) doped superatom (HPd@Au(8))(+) protected by eight PPh(3) ligands selectively grew into (HPd@Au(10))(3+) by the nucleophilic addition of two Au(I)Cl units. In the present study, (HPd@Au(8))(+) was successfully converted to unprecedented trimetallic (HPd@M(2)Au(8))(3+) superatoms (M = Ag, Cu) by controlled doping of two Ag(I)Cl or Cu(I)Cl units, respectively. Single-crystal X-ray diffraction analysis demonstrated that two Ag(I) or Cu(I) ions were regioselectively incorporated. Theoretical calculations suggested that hydrogens in (HPd@M(2)Au(8))(3+) (M = Au, Ag, Cu) occupy the same bridging site between the central Pd atom and the surface Au atom. (HPd@Ag(2)Au(8))(3+) exhibited photoluminescence at 775 nm, with the enhanced quantum yield of 0.09%, although it is structurally and electronically equivalent with (HPd@Au(10))(3+). This study demonstrates that hydride-mediated growth process is a promising atomically-precise bottom-up synthetic method of new multimetallic superatoms.