215670-11-4Relevant academic research and scientific papers
Synthesis, spectroscopy and crystal structures of [Au2{μ-Ph2PN(Et)PPh2}2][SbF 6]2 and [Au3Cl2{μ-Ph2PN(Et)PPh2} 2]PF6
Field, John S.,Grieve, Judith,Haines, Raymond J.,May, Noellene,Zulu, Mthembeni M.
, p. 3021 - 3029 (1998)
Treatment of [Au(MeCN)2]SbF6 in acetonitrile with bis(diphenylphosphino)ethylamine (dppa) afforded a colourless crystalline material characterised as [Au2(μ-dppa)2] [SbF6]2. An X-ray diffraction study confirmed that the two ligands bridge the two gold atoms with a Au...Au separation of 2.838(2) A. The electronic absorption spectrum exhibits a band at 298 nm (∈max, ca. 17000 dm3mol-1cm-1) attributable to a pσ?dσ* transition. The compound luminesces strongly in acetonitrile (λmax = 500 nm). Treatment of HAuCl4.2H2O with 2,2′-thioethanol in methanol followed by the ligand afforded a colourless crystalline material characterised as [Au3Cl2(μ-dppa)2]PF6. A crystal structure determination revealed a cation of C2 symmetry, comprising a bent chain of three gold atoms (Au...Au...Au= 167.5(8)°, Au...Au = 3.037(1)A), with each pair of adjacent gold atoms bridged by a diphosphazane ligand and with the coordination at the outer gold atoms completed by a chloride ligand. This compound luminesces extremely weakly in acetonitrile but does emit strongly at 485 nm when irradiated in the solid state. The luminescence displayed by both compounds is attributed to the presence of a substantial intramolecular interaction between the gold atoms, but ligand effects appear to be more important in determining the emissive energies.
