Bahng Hee-Won, Ertl Cathrin D, Yuan Jennifer, Wolf Michael O
Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada.
J Phys Chem Lett. 2023 Nov 23;14(46):10369-10377. doi: 10.1021/acs.jpclett.3c02468. Epub 2023 Nov 10.
Light-driven changes in supramolecular interactions in perylene bisimides (PBIs) with pendant sulfur-containing functional groups at the bay position are demonstrated. In the ground state, a noncovalent S···X interaction between the σ-hole on sulfur and a heteroatom, X (X = O, N, S), of a neighboring molecule is the main driving force for intermolecular interactions, while in the excited state it is the π-π interaction between PBI scaffolds which drives assembly. The presence of heteroatoms in the solvent results in acceleration of the π-stacking process via the formation of a PBI-solvent complex. The excited-state dynamics involved in the assembly process were revealed via time-resolved fluorescence and transient absorption spectroscopies, while steady-state spectroscopy was used to evaluate the structure of the supramolecular assembly.
研究表明，在湾区带有含硫官能团侧链的苝二酰亚胺（PBI）中，光驱动会引起超分子相互作用的变化。在基态下，硫上的σ-空穴与相邻分子的杂原子X（X = O、N、S）之间的非共价S···X相互作用是分子间相互作用的主要驱动力，而在激发态下，是PBI支架之间的π-π相互作用驱动组装。溶剂中杂原子的存在通过形成PBI-溶剂复合物加速了π-堆积过程。通过时间分辨荧光和瞬态吸收光谱揭示了组装过程中涉及的激发态动力学，同时使用稳态光谱来评估超分子组装体的结构。
