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Cationic PtAu2 heterotrinuclear complexes [PtAu2(dpmp)2(C≡CR)2]2+ (dpmp = bis(diphenylphosphinomethyl)phenylphosphine, R = aryl) of aromatic acetylides were prepared. The PtAu2 structures are supported through doubly bridging dpmp and stabilized by a significant Pt–Au interaction. They are highly phosphorescent in fluid CH2Cl2 solution (Φem = 23.5%–78.9%), the solid state (Φem = 15.4%–70.2%), the PMMA film (Φem = 39.9%–71.7%) and the doping film of 61% TCTA : 31% OXD-7 : 8% PtAu2 complex (Φem = 16.9%–67.9%). The phosphorescence arises mainly from 3[π (C≡CR) →π* (dpmp)] 3LLCT and 3[π (C≡CR) → s/p (PtAu2)] 3LMCT triplet excited states for carbazole-acetylide complexes, whereas other complexes display a 3LLCT character mixed with noticeable PtAu2 centered 3[d → s/p] parentage. Utilizing a mixed host composed of hole-transporting TCTA and electron-transporting OXD-7 doped with 8% PtAu2 species as a light-emitting layer and CuSCN as a hole-transporting layer through an orthogonal solution process, the devices exhibit highly efficient electrophosphorescence with the highest current efficiency (CEmax) of 51.7 cd A−1 and external quantum efficiency (EQEmax) of 14.5%. The efficiency roll-off is small in the practical brightness range of 500–5000 cd m−2. The PtAu2 complexes with carbazole-acetylides display a higher electroluminescence efficiency ascribed to their better hole-transporting character as well as more facile energy transfer from mixed host materials. [ABSTRACT FROM AUTHOR]

Heterodimetallic Ru–Fe complexes [(tppz)(PPh3)2RuL](ClO4) (L = C≡CFc, [1](ClO4); C≡C–C6H4–C≡CFc), [2](ClO4); C≡C–C6H4–C6H4–C≡CFc, [3](ClO4)) were synthesized by the reactions of [(tppz)(PPh3)2RuCl](ClO4) (tppz = 2,3,5,6-tetrakis(2-pyridyl)pyrazine) with ferrocence-acetylide ligands and characterized by ESI-MS, and 1H and 31P NMR spectroscopies. The structure of [1](PF6) was determined by X-ray crystallography. The electrochemical studies show that compounds [1](ClO4)–[3](ClO4) possess two widely separated anodic peaks, ascribable to one-electron oxidation of Fc and RuII, respectively. This assignment is further corroborated by the results of UV-vis-NIR, XPS, and theoretical calculation studies. Compound [1](ClO4) exhibits significant Ru…Fe metal–metal interactions across the Ru–C≡C–Fc backbone. As revealed by electrochemical, spectroscopic and theoretical computational studies, one-electron oxidized species [1a](ClO4)2 is between the electronically delocalized and valence-trapped state and shows a typical Robin–Day class II mixed-valence behavior. [ABSTRACT FROM AUTHOR]

The synthesis, structure, and phosphorescence properties of twofamilies of triphosphine-supported Au(I)–Ag(I) heteronuclearalkynyl cluster complexes with unprecedented Au2Ag2and Au8Ag4cluster structures are described.The phosphorescence emission over the whole visible light region wassystematically tuned through modification of the electronic effectsin aromatic acetylide ligands to attain bright phosphorescence withdifferent luminescent colors. Introduction of electron-withdrawingCF3to phenylacetylides results in the emission spectralblue-shift, while it shows progressive red-shift upon introducingelectron-donating But, OMe, or NMe2. As demonstratedfrom both experimental and theoretical studies, the phosphorescencearises primarily from 3LLCT/3IL and Au2Ag2/Au8Ag4cluster-centered 3[d→p] transitions. [ABSTRACT FROM AUTHOR]