Dipartimento di Chimica GIAF and INSTM-UdR Parma, Università degli studi di Parma, Parco Area delle Scienze 17/a, 43124 Parma, Italy.
J Phys Chem B. 2011 Oct 6;115(39):11420-30. doi: 10.1021/jp206592s. Epub 2011 Sep 9.
An extensive spectroscopic study is presented of two asymmetrically substituted fluorene dyes and of the related spiro dimers in both liquid and glassy solvents. Essential-state models are developed to accurately reproduce linear absorption and fluorescence spectra and their complex dependence on solvent polarity. The same models are exploited to quantitatively calculate fluorescence excitation and anisotropy spectra in rigid matrixes. Impressive red-edge effects observed for spiro dimers in glassy polar solvents are accurately reproduced and understood. Interchromophore interactions in the spiro dimers are very small, leading to marginal effects in absorption and fluorescence spectra, but they effectively promote energy transfer between the two chromophores, as best evidenced comparing anisotropy spectra of the substituted fluorenes and of corresponding spiro dimers dissolved in glassy solvent matrixes.
本文对两个不对称取代芴染料和相关的螺二聚体在液体和玻璃溶剂中的光谱进行了广泛的研究。开发了基本状态模型来准确地再现线性吸收和荧光光谱及其对溶剂极性的复杂依赖性。相同的模型被用于在刚性基质中定量计算荧光激发和各向异性光谱。在玻璃状极性溶剂中观察到的螺二聚体令人印象深刻的红移效应被准确地再现和理解。螺二聚体中的发色团间相互作用非常小，导致吸收和荧光光谱的影响不大，但它们有效地促进了两个发色团之间的能量转移，这在比较溶解在玻璃溶剂基质中的取代芴和相应的螺二聚体的各向异性光谱时得到了最好的证明。
