A Mixed-Valence Superstructure Assembled from A Mixed-Valence Host-Guest Complex
Zhichang Liu, Marco Frasconi, Wei-Guang Liu, Yu Zhang, Scott M. Dyar, Dengke Shen, Amy A. Sarjeant, William A. Goddard III, Michael R. Wasielewski, J. Fraser Stoddart
Abstract
Herein, we report an unprecedented mixed-valence crystal superstructure that consists of a 2:1 host–guest complex [MV⊂(CBPQT)_2]^(2/3+) [MV = methyl viologen, CBPQT = cyclobis(paraquat-p-phenylene)]. One electron is distributed statistically between three [MV⊂(CBPQT)_2]•+ composed of a total of 15 viologen units. The mixed-valence state is validated by single-crystal X-ray crystallography, which supports an empirical formula of [MV⊂(CBPQT)_2]_3·(PF_6)_2 for the body-centered cubic superstructure. Electron paramagnetic resonance provides further evidence of electron delocalization. Quantum chemistry calculations confirm the mixed-valence state in the crystal superstructure. Our findings demonstrate that precise tuning of the redox states in host–guest systems can lead to a promising supramolecular strategy for achieving long-range electron delocalization in solid-state devices.
Group Members
Liu, Z., Frasconi, M., Liu, W., Zhang, Y., Dyar, S. M., Shen, D., Sarjeant, A. A., III, W. A. G., Wasielewski, M. R., & Stoddart, J. F. (2018). A Mixed-Valence Superstructure Assembled from A Mixed-Valence Host-Guest Complex. *J. Am. Chem. Soc.*, *140*(30), 9387-9391. https://doi.org/10.1021/jacs.8b05322