Fractals and Excitation Transfer in Molecular Assemblies

电子激发转移已经研究了若干种分子集合的分子集合，如vesicles和Langmuir-Blodgett电影，并通过一个视图来建立在来宾分子分布中的分形结构。激发转移的动力学是由一个像素时间分解的荧光光谱仪的意思来调查的。它发现了一种分形行为，即分子组件在空间分布中或在现场-能量分布，以及分子组件框架的形态学对能量松弛过程的动力学产生影响。荧光的变化可以通过一个等式来分析，其中包括一个拉伸的表达式函数。单一激发能量放松的机制在（1）术语下解释的接受者位点在分形分布下的分形尺寸为1.3 - 1.5，和（2）超计量空间中能源失调的单体站点中的能量迁移（层次能量分布）：激发能量传输的扩散长度被估计为从动力股票转移和荧光衰减曲线转移。

Electronic excitation transfer has been studied with several kinds of molecular assemblies such as vesicles and Langmuir-Blodgett films with a view to establishment of the fractal structure in distribution of guest molecules. Dynamics of excitation transfer was investigated by means of a picosecond time-resolved fluorescence spectrophoto-meter. It was found that the fractal behaviors are essential among molecular assemblies in spatialdistribution of chromophores or in siteーenergy distribution, and that the morphology of molecular assembly frameworks affects the dynamics of energy relaxation processes. The fluorescence decays can be analyzed by an equation including a stretched exponential function. The mechanisms of singlet excitation energy relaxation were interpreted in terms of(1) the energy trapping at acceptor sites under the fractal distribution with the fractal dimension of 1.3 -1.5, and(2) the energy migration among energetically disordered monomer sites represented by ultrametric space (hierarchical energy distribution).The diffusion length of the excitation energy transport was estimated from the dynamic stokes shift and the fluorescence decay curve.