Picosecond kinetics of the excited-state, proton-transfer reaction of 1-naphthol in water
Picosecond kinetics of the excited-state, proton-transfer reaction of 1-naphthol in water
复制标题
1-萘酚在水中激发态质子转移反应的皮秒动力学
DOI：
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发表时间：
1986
期刊：
影响因子：
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通讯作者：
J. Clark
中科院分区：
文献类型：
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作者：
S. Webb;L. Philips;S. Yeh;L. Tolbert;J. Clark
研究了1-萘酚在H/sub 2/O和D/sub 2/O体系中激发态质子转移反应的详细动力学。这一过程的研究，同时使用皮秒，时间分辨发射光谱和稳态荧光光谱。通过使用这些实验的结果，开发了详细的ESPT动力学模型。计算机模拟被用来评估这个动力学模型的预测与实际的时间和光谱数据在广泛的实验条件下进行比较。根据这些分析，1-萘酚中激发态质子转移和再质子化速率分别为2.5 × 10/sup 10/ s/sup-1/和6.8 × 10/sup 10/ M/sup-1/ s/sup-1/（pK/sub a/* = 0.4）和7.9 × 10/sup 9/ s/sup-1/和4.8 × 10/sup 10/ M/sup-1/ s/sup-1/在D/sub 2/O（pK/sub a/* = 0.8）中。还确定了1-萘酚的ESPT反应的完整和准确的描述所需的其他速率常数。关于溶质/溶剂系统的性质的问题进行了讨论相对于激发态过程中的溶剂的效果。还考虑使用质子转移过程作为溶剂相互作用的探针。
The detailed kinetics of the excited-state, proton-transfer (ESPT) reaction of 1-naphthol in H/sub 2/O and D/sub 2/O are investigated. This process is studied by using both picosecond, time-resolved emission spectroscopy and steady-state spectrofluorometry. A detailed model of the ESPT kinetics is developed by using the results of these experiments. Computer simulations are used to evaluate the predictions of this kinetic model by comparison with the actual temporal and spectral data taken over a wide range of experimental conditions. On the basis of such analyses, the rates for excited-state proton transfer and reprotonation in 1-naphthol are 2.5 x 10/sup 10/ s/sup -1/ and 6.8 x 10/sup 10/ M/sup -1/ s/sup -1/ in H/sub 2/O (pK/sub a/* = 0.4) and 7.9 x 10/sup 9/ s/sup -1/ and 4.8 x 10/sup 10/ M/sup -1/ s/sup -1/ in D/sub 2/O (pK/sub a/* = 0.8), respectively. The other rate constants necessary for a complete and accurate description of the ESPT reaction of 1-naphthol are also determined. Questions regarding the nature of the solute/solvent system are discussed with respect to the effect of the solvent on the excited-state processes. The use of the proton-transfer process as a probe of solvent interactions is also considered.