咔唑与N-烷基咔唑光物理行为的差异

已知甲基、乙基咔唑等咔唑的衍生物与对位苯二甲酸二甲酯(DMTP)和邻位苯二甲酸二甲酯(DMP)可以形成激基复合物^1],但是咔唑与DMTP或DMP相互作用时观察不到激基复合物的荧光。

DIFFERENCE IN PHOTOPHYSICAL BEHAVIOR BETWEEN CARBAZOLE AND N-ALKYL CARBAZOLE

The fluorescence spectra of carbazole and N-ethyl carbazole mixed with DCB and chloro substituted benzene were studied in this paper. The photophysical behavior of carbaaole was quite different from N-alkyl carbazole derivatives. Exciplex may not be formed between carbazole and various acceptors. Only quenching of carbazole fluorescence can be observed. We proposed that the reasonable explanation is due to the difference in electrical density in N-atom of carbazole and N-alkyl carbazole derivatives. Current theoretical and experimental results indicate N-alkylation of carbazole has a substantial effect on the nitrogen "lone electron pair". Electron density on nitrogen is increased Lowering of electron density on nitrogen will promote the formation of encounter complex which causes the quenching of fluorescence and restricts the conversion of encounter complex to equilibrium exciplex. Chlorosubstituted benzene were used to check this assumption. The experimental results support our proposal.