Zhang Jian, Xu Hengyue, Fang Weifeng, Liu Xin, Zhang Haoke, Tang Ruikang, Liu Zhaoming
Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang, 310027, China.
Department of Chemistry, Tsinghua University, Beijing, 100084, China.
Angew Chem Int Ed Engl. 2025 Jan 15;64(3):e202415664. doi: 10.1002/anie.202415664. Epub 2024 Nov 16.
Locking molecular conformation are widely applied in molecular engineering for improved performance. However, locking via organic functional groups often changes the original molecular properties. Following the rigidity and stability of ionic interaction in ionic compounds, we suggested the use of a molecular-scale ionic compound, calcium carbonate oligomer, as a robust molecular segment to functionalize organic molecules. The rigid structure of the ionic molecular segments locked the organic molecules, which could remarkably limit the intramolecular motion and intermolecular interactions. This ensured a stable and ultrastrong fluorescence of the single organic molecule while preserving its original maximum emission wavelength. The locking strategy was general and extendable to multiple organic molecules. Additionally, the ultrastrong single-molecular fluorescence can be maintained in inorganic solids with even higher quantum yields and almost unchanged maximum emission wavelength. The highest quantum yield of the investigated molecules reached 99.9 %, superior to all reported organic-inorganic fluorescent composite under air conditions. This work demonstrates a general strategy to restrict intramolecular motion and intermolecular interactions by using ionic oligomers as molecular locks, providing an alternative method for realizing ultraemissive molecules. This further demonstrates a fascinating example of molecular engineering in the presence of inorganic ionic molecules.
锁定分子构象在分子工程中被广泛应用以提高性能。然而，通过有机官能团进行锁定常常会改变原始分子的性质。基于离子化合物中离子相互作用的刚性和稳定性，我们建议使用一种分子尺度的离子化合物——碳酸钙低聚物，作为一种强大的分子片段来官能化有机分子。离子分子片段的刚性结构锁定了有机分子，这可以显著限制分子内运动和分子间相互作用。这确保了单个有机分子具有稳定且超强的荧光，同时保持其原始的最大发射波长。这种锁定策略具有通用性，可扩展到多种有机分子。此外，在无机固体中可以保持超强的单分子荧光，量子产率甚至更高，最大发射波长几乎不变。所研究分子的最高量子产率达到99.9%，优于在空气条件下所有已报道的有机 - 无机荧光复合材料。这项工作展示了一种通过使用离子低聚物作为分子锁来限制分子内运动和分子间相互作用的通用策略，为实现超发光分子提供了一种替代方法。这进一步展示了在无机离子分子存在下分子工程的一个引人入胜的例子。
