{[Ag2 (μ-dppm)2 (μ-TCNQ)2](TCNQ)}, a charge transfer compound derived from a donor with a metal–metal bond

Reaction of AgNO3, dppm (bis(diphenylphosphino)methane), and TCNQ in molar ratio of 1 : 1 : 1 produced an acceptor–donor silver compound {[Ag2(dppm)2 (µ-TCNQ)2](TCNQ)}, 1. In the structure, determined by X-ray crystallography, two silver atoms are triply-bridged by two dppm ligands and metal–metal bond to form a dimer; the distance between two Ag is 3.1753(8) Å. Compound 1 was studied by IR and UV/Vis/NIR spectroscopy, exhibiting an intervalence transfer transition at λ = 1286 nm, and also is photoluminescent (λmax = 537 and 654 nm) at room temperature.