Fluorescence quantum yield oxadiazoles

The absorption (A ax 402nm, logs 4.71) and emission (A ax 453, 477nm) maxima, fluorescence quantum yields, and the optical energy of 2,5-bis[5-(4,5,6,7-tetrahydrobenzo[b]thien-2-yl)thien-2-yl]-l,3,4-oxadiazole 20 were studied in dichloromethane <1998CEJ2211>. 

Diaryl-l,3,4-oxadiazoles exhibit strong fluorescence in solution on stimulation by UV or /3-irradiation, particularly 2-biphenylyl-5-phenyl- and 2-biphenyl-5-(l-naphthyl)-l,3,4-oxadiazole (cf. Section V). The quantum yield of the 1,3,4-oxadiazoles is lower than with p-terphenyl and its analogs.163-155 The band intensity with unsubstituted aryl-1,3,4-oxadiazoles and aromatic substituted oxadia-zoles is essentially the same.155... 

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