Tang Tingji, Herrmann Andreas, Peneva Kalina, Müllen Klaus, Webber Stephen E
Department of Chemistry and Biochemistry and Center for Nano and Molecular Science, The University of Texas at Austin, Austin, Texas 78712, USA.
Langmuir. 2007 Apr 10;23(8):4623-8. doi: 10.1021/la0634903. Epub 2007 Mar 13.
Multilayer films of water-soluble anionic and cationic perylene diimide (PDI) moieties have been prepared using the molecular layer-by-layer method described in an earlier publication (Tang, T. J.; Qu, J. Q.; Müllen, K.; Webber, S. E. Langmuir 2006, 22, 26-28) and the fluorescence intensity compared with and without a base layer prepared using an anionic terrylene diimide dye (n-TDI), which serves as an energy-trapping layer for the PDI exciton. The fluorescence quenching data could be fit equally well to a modification of a model used by Kuhn to describe energy transfer from a J aggregate or a model developed by Kenkre and Wong to describe excitonic transfer. For both models, we obtain a characteristic energy-transfer distance on the order of 5.4 nm. Fluorescence quenching of the PDI via a single Förster energy-transfer step to the n-TDI layer is ruled out on the basis of the observed power-law dependence. We also consider a model in which the excitation is trapped at the outermost surface. This model provides a reasonable fit to the data only if the Kuhn relationship is used.
利用早期出版物（Tang, T. J.; Qu, J. Q.; Müllen, K.; Webber, S. E. Langmuir 2006, 22, 26 - 28）中描述的分子层层组装方法，制备了水溶性阴离子和阳离子苝二酰亚胺（PDI）部分的多层膜，并将其荧光强度与使用阴离子并四苯二酰亚胺染料（n - TDI）制备的有无基层的情况进行了比较，该染料用作PDI激子的能量捕获层。荧光猝灭数据可以同样好地拟合库恩用于描述从J聚集体的能量转移的模型的修正版，或者肯克雷和王开发的用于描述激子转移的模型。对于这两个模型，我们得到的特征能量转移距离约为5.4 nm。基于观察到的幂律依赖性，排除了通过单个福斯特能量转移步骤将PDI的荧光猝灭到n - TDI层的情况。我们还考虑了一种激发被困在最外表面的模型。只有使用库恩关系时，该模型才能合理地拟合数据。
