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Updated: Sep 26, 2025

Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
Modulation of π character upon complexation captured by molecular rotation spectra
Yang Zheng1,2, Qin Yang2, Sven Herbers3
1Department of Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, No. 55 Daxuecheng South Rd., Shapingba, Chongqing, 401331, China. qian.gou@cqu.edu.cn.
Abstract:
Two configurations of the furan-CF3Cl complex have been observed by high-resolution rotational spectroscopy. One is characterized by a dominant Cl lone pair⋯π*aromatic interaction and the other is stabilized by a C-Cl···π-CC- halogen bond. This is the first rotational spectroscopic evidence, to the best of our knowledge, that shows how a complexation with a partner like CF3Cl (the weak lone pair belt of Cl, to be more specific) can modulate both the aromatic π* and diene π characters of a heteroaromatic molecule in the formation of non-covalent interactions. The results emphasize the partner molecules' role in modulating the π electron structure and will not only deepen our understanding on non-covalent interactions but also lead to better designs of heteroaromatic-based drugs and materials.
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