【摘要】 <正> 芘是一种很好的电子转移试剂,它既可以作为电子给体,又可以作为电子受体。因此,在电子转移光化学、光物理中有不少研究文章报导。由于其较强的荧光、较高的量子产率及较长的荧光寿命,因而常被用作荧光探针,研究胶体分子及生物大分子的结构和功能等。利用紫外、红外、电子脉冲辐射和激光光解瞬态光导的测量方法研究芘与一些溶剂的相互作用以及在不同极性溶剂中的光离子化现象已有一些研究工作。本文报导芘在不同极性溶剂中的时间分辨瞬态吸收光谱的研究结果。藉对芘在不同极性溶剂中的时间分辨瞬态吸收光谱的研究,了解芘在不同极性溶剂中的瞬态反应过程,考查其与溶剂间在激光作用下的相互作用。更多还原

【Abstract】 The transient processes of pyrene （Py） have been studied by measuring fluores-cence lifetime and nanosecond time-resolved transient absorption spectra in n-hexane,cyclohexane, acetone, and acetonitrile. The single exponential decay for pyrene-hexaneand pyrene-oyclohexane systems were observed, yet the double exponential decay wereshown for the pyrene-acetone and pyrene-acetonitrile systems （Table 1 of the Chinesetext）. In the transient absorption spectra,the absorbance of excited triplet pyrene wasobserved for the four systems （Fig. 1--4,of the Chinese text）. In addition, the ab-sorption band of the pyrene cation radical, which was not quenched by O₂, was alsoobserved for the pyrene-acetonitrile system （Fig. 2 of the Chinese text）. This resultclearly demonstrate that there are interaction between pyrene and acetonitrile andpyrene cation radical is formed by electron transfer from the excited singlet state ofpyrene to acetonitrile. According to experimental results, the photophysical mechanismfor the four systems was suggested.更多还原