在液体-液体界面上通过时间解析的表面第二波生成以亚分子空间分辨率研究激发的半氨酸的非辐射失活
Gaelle Martin-Gassin1, Diego Villamaina, Eric Vauthey
1Department of Physical Chemistry, University of Geneva, Genève, Switzerland.
Journal of the American Chemical Society
|February 10, 2011
概括
氨基色素染料的兴奋状态动态涉及非辐射失活. 这项研究表明,受无极相粘度影响的dialkylaniline组的扭曲是这一过程的原因.
科学领域:
- 摄影化学的使用.
- 化学物理 化学物理
- 染料化学 染料化学
背景情况:
- 氨基酸染料表现出由非辐射失活主导的兴奋状态动态.
- 大幅度的分子运动是这种失活过程中的关键因素.
研究的目的:
- 为了确定特定的分子坐标 (s) 驱动非辐射失活在aminostilbazolium染料.
- 为了研究界面粘度对激发状态生命周期的影响.
主要方法:
- 测量了两个dialkylaminostyryl-methylpyridinium iodides的兴奋状态寿命.
- 在液体-液体接口上使用时间解析表面第二波生成 (TR-SSHG).
- 改变了无极 (n-) 和极 (水/糖醇) 阶段的粘度.
主要成果:
- 激发状态衰变时间随着无极相的粘度增加而增加.
- 激发状态衰变时间不受极相粘度的影响.
- 观察到的行为表明,特定的分子运动是导致失活的原因.
结论:
- 这些染料的非辐射失活主要与dialkylaniline组的扭曲有关.
- 这种运动发生在分子环境的无极区域内.
- 界面粘度在调节激发状态动态方面发挥着至关重要的作用.
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