Preferential solvation of coumarin 153 -: The role of hydrogen bonding
Preferential solvation of coumarin 153 -: The role of hydrogen bonding
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DOI：
10.1021/jp013916g
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发表时间：
2002-03-07
影响因子：
2.9
通讯作者：
Lampre, I
中科院分区：
文献类型：
--
作者：
Królicki, R;Jarzeba, W;Lampre, I
本文研究了溶剂化显色探针香豆素153在甲苯-乙腈和甲苯-甲醇混合溶剂中的优先溶剂化作用。香豆素153在这些非理想体系中的吸收光谱和荧光光谱的溶剂化变色位移作为溶剂极性的函数进行了分析。香豆素153在基态没有明显的优先溶剂化作用。对于激发态分子优先溶剂化甲苯-乙腈混合物中观察到，它是由一个理论模型证实。对于激发态C153在甲苯-甲醇混合物中的荧光溶剂化变色位移的强非线性主要归因于甲醇和C153之间形成氢键。C153在含有甲醇的溶剂混合物中的红外光谱证实了甲醇和C153之间形成氢键。在甲苯-甲醇混合物中氢键C153的存在导致C153荧光寿命对溶液中甲醇的摩尔分数的不寻常的依赖性。
Preferential solvation of solvatochromic probe coumarin 153 has been studied in toluene-acetonitrile and toluene-methanol solvent mixtures. Solvatochromic shifts of absorption and fluorescence spectra of coumarin 153 in these nonideal systems are analyzed as a function of solvent polarity. There is no apparent preferential solvation of coumarin 153 in the ground state. For the excited-state molecule preferential solvation is observed in toluene-acetonitrile mixtures and it is confirmed by a theoretical model. For the excited C153 in toluene-methanol mixtures strong nonlinearity in the fluorescence solvatochromic shifts is attributed mainly to formation of a hydrogen bond between methanol and C153. IR spectra of C 153 in solvent mixtures containing methanol confirm formation of a hydrogen bond between methanol and C153. The presence of a hydrogen-bonded C153 in toluene-methanol mixtures causes an unusual dependence of the C153 fluorescence lifetime on the mole fraction of methanol in solution.