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A dpppy-protected (dpppy = 2,6-bis(diphenylphosphino)pyridine) d10–d10 heterooctanuclear cluster complex [Ag3Cu5(ebzcz)6(dpppy)3](ClO4)2 (Hebzcz = 1-(3,6-di-tert-butylcarbazol-9-yl)-4-ethynylbenzene) was prepared by self-assembly reaction and characterized by single crystal X-ray diffraction. The diphosphine-supported Ag3Cu5 cluster structure is highly stabilized through substantial Cu–Ag and Cu–Cu intermetallic interactions. Since the Ag3Cu5 cluster is sufficiently shielded by bulky ligands (three ebzcz and three dpppy), thermally non-radiative relaxation is strongly prohibited so as to give brilliant photoluminescence under ambient conditions. As revealed by TD-DFT studies, the luminescence arises from metal cluster-centred 3[d → p/s] and 3[π (ebzcz) → π* (dpppy)] 3LLCT (ligand-to-ligand charge transfer) transitions. Taking advantage of Ag3Cu5 cluster complex as a phosphorescent dopant, a high-efficiency solution-processed organic light-emitting diode is achieved with a peak current efficiency of 38.1 cd A−1, a power efficiency of 29.9 lm W−1 and an external quantum efficiency of 14.7%. [ABSTRACT FROM AUTHOR]

A feasible synthetic approach to achieve Ag8, Ag16 and Ag29 silver(i) nanoclusters is reported by the use of 1,8-diethynyl-9H-carbazole (H3decz) as a directing ligand. The silver(i) nanoclusters exhibit room-temperature photoluminescence in both solution and solid state. The emission band shows stepwise red-shifts from visible to near-infrared region with the increase of cluster nuclearity following 2 (Ag8, λem = 571 nm) →3 (Ag16, λem = 651 nm) →4 (Ag29, λem = 916 and 875sh nm) in fluid CH2Cl2. [ABSTRACT FROM AUTHOR]