Faculty of Chemical Technology and Engineering, University of Technology and Life Sciences, Seminaryjna 3, 85-326, Bydgoszcz, Poland.
J Fluoresc. 2010 Jan;20(1):73-86. doi: 10.1007/s10895-009-0524-5. Epub 2009 Aug 13.
The study on the relationship between the structure and spectroscopic properties of styrylquinolinium dyes were carried out by measuring the electronic visible absorption, steady-state and time-resolved fluorescence spectra of quinoline based hemicyanine dyes. The influence of the solvent on absorption and emission spectra and the solvatochromic properties, observed for both ground and first excited states, for all the dyes were applied for the evaluation of their excited state dipole moments. The ground state dipole moments of dyes under the study were established by applying ab initio calculations. The measured, using solvatochromic methods, excited state dipole moments of tested hemicyanines are in the range from 5.38 to 18.90 D and the change in the dipole moments caused by excitation were found to differ from 1.88 to 6.64 D. It was observed that for all tested dyes the dipole moments of the excited states were higher than those of a ground states. The fluorescence lifetime measurements with picosecond resolution was performed for entire series of hemicyanine dyes possessing different dialkylamino groups attached to the phenyl ring. The average lifetimes of the dye fluorescence, determined from the measured data by multi-order exponential decay curve fitting, were in the range from about 120 to 1200 ps at the fluorescence peak wavelength. The fluorescence lifetime measurements were performed for dyes in ethyl acetate solutions. The time-resolved fluorescence spectra measurements allowed to propose the mechanism of the dyes excited states deactivation.
通过测量基于喹啉的半花菁染料的电子可见吸收、稳态和时间分辨荧光光谱，研究了苯乙烯基喹啉鎓染料的结构与光谱性质之间的关系。溶剂对吸收和发射光谱的影响以及观察到的基态和第一激发态的溶剂变色性质，用于评估它们的激发态偶极矩。通过应用从头算计算，确定了研究中染料的基态偶极矩。使用溶剂变色法测量的测试半花菁的激发态偶极矩在 5.38 至 18.90 D 范围内，激发引起的偶极矩变化在 1.88 至 6.64 D 之间。观察到对于所有测试的染料，激发态的偶极矩均高于基态的偶极矩。使用皮秒分辨率进行了整个系列具有不同二烷基氨基取代苯基环的半花菁染料的荧光寿命测量。通过多阶指数衰减曲线拟合从测量数据确定的染料荧光平均寿命，在荧光峰波长处约为 120 至 1200 ps。荧光寿命测量是在乙基乙酸酯溶液中的染料中进行的。时间分辨荧光光谱测量允许提出染料激发态失活的机制。
