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Title: Synthesis, structure and photophysical properties of a 2D network with gold dicyanide donors coordinated to aza[5]helicene viologen acceptors
A recently synthesized photoluminescent organic acceptor, 5,10-dimethyl-5,10-diaza[5]helicene is shown to react with dicyanoaurate anions to form a 2D network N , N -dimethylaza[5]helicene dicyanoaurate. The structure of the synthesized complex was investigated via X-ray crystallography showing the presence of [Au(CN) 2 ] − dimers and monomers within the helicene framework. Photophysical measurements between 298 K and 10 K indicate quenching of the [Au(CN) 2 ] − anion by 5,10-dimethyl-5,10-diaza[5]helicene via an electron transfer. A Stern–Volmer and Rehm–Weller analysis shows that this is a result of quenching from transfer of an electron from [Au(CN) 2 ] − anions to 5,10-dimethyl-5,10-diaza[5]helicene as opposed to resonance energy transfer. DFT calculations were performed to support the assignment of an electron transfer.
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Dalton Transactions
Page Range or eLocation-ID:
10288 to 10297
Sponsoring Org:
National Science Foundation
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