Univ. Lille, CNRS, UMR 8516, LASIR, Laboratoire de Spectrochimie Infrarouge et Raman, F59 000 Lille, France.
Université Paris Diderot, Sorbonne Paris Cité, 5 rue Thomas Mann, 75205 Paris Cedex 13, France and Chimie Paris Tech, PSL Research University, CNRS, Institut de Recherche de Chimie Paris (IRCP), F-75005 Paris, France.
Phys Chem Chem Phys. 2019 Mar 28;21(12):6407-6414. doi: 10.1039/c8cp07100d. Epub 2019 Mar 6.
The excited state dynamics of constrained photochromic benzodithienylethenes were addressed by considering the bridging with polyether chains (from x = 4 to 6 units) at the ortho and meta positions of the aryl group, named DTE-o and DTE-m, via time-resolved absorption spectroscopy supported with (TD)-DFT calculations. The photochromic parameters and geometrical structures of these series are discussed. A novel photocyclization pathway via a triplet state, evidenced recently (Hamdi et al., Phys. Chem. Chem. Phys., 2016, 18, 28091-28100), is largely dependent on the length and the position of the polyether chain. For the first time, by comparing the two series, we revealed, for the DTE-o series, an interconversion not only in the ground state but also between the triplet states of the anti-parallel and parallel open form conformers.
通过考虑在芳基的邻位和间位处用聚醚链（x 从 4 个到 6 个单元）桥接，研究了受限光致变色苯并二噻吩乙烯的激发态动力学，分别命名为 DTE-o 和 DTE-m，通过时间分辨吸收光谱和（TD）-DFT 计算得到支持。讨论了这些系列的光致变色参数和几何结构。最近（Hamdi 等人，Phys. Chem. Chem. Phys.，2016，18，28091-28100）证明了一种通过三重态的新型光环化途径，该途径在很大程度上取决于聚醚链的长度和位置。我们首次通过比较两个系列，揭示了 DTE-o 系列不仅在基态而且在反平行和平行开形式构象的三重态之间存在互变。
