A single solvating benzene molecule decouples the mixed-valence complex through intermolecular orbital interactions

• Published in: iScience Vol. 25; no. 6; p. 104365
• Main Authors: Mallick, Suman, Zhou, Yuli, Chen, Xiaoli, Tan, Ying Ning, Meng, Miao, Cao, Lijiu, Qin, Yi, He, Zi Cong, Cheng, Tao, Zhu, Guang Yuan, Liu, Chun Y.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 17.06.2022; Elsevier
• Subjects: Chemistry; Organic chemistry; Physical organic chemistry; Organic chemistry; Chemistry; Physical organic chemistry
• ISSN: 2589-0042; 2589-0042
• DOI: 10.1016/j.isci.2022.104365

Characterization of covalency of intermolecular interactions in the van der Waals distance limit remains challenging because the interactions between molecules are weak, dynamic, and not measurable. Herein, we approach this issue in a series of supramolecular mixed-valence (MV) donor(D)-bridge(B)-acceptor(A) systems consisting of two bridged Mo2 units with a C6H6 molecule encapsulated, as characterized by the X-ray crystal structures. Comparative analysis of the intervalence charge transfer spectra in benzene and dichloromethane substantiates the strong electronic decoupling effect of the solvating C6H6 molecule that breaks down the dielectric solvation theory. Ab initio and DFT calculations unravel that the intermolecular orbital overlaps between the complex bridge and the C6H6 molecule alter the electronic states of the D-B-A molecule through intermolecular nuclear dynamics. This work exemplifies that site-specific intermolecular interaction can be exploited to control the chemical property of supramolecular systems and to elucidate the functionalities of side-chains in biological systems. [Display omitted] •Decoupling mixed-valence complexes by an encapsulated benzene molecule•Demonstrating intermolecular orbital interactions in the van der Waals distances•Illustrating interplay between intermolecular electronic and nuclear degrees of freedom Chemistry; Organic chemistry; Physical organic chemistry