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Updated: Jan 25, 2026

Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
Indeno[1,2-b]fluorene-Based [2,2]Cyclophanes with 4n/4n and 4n/[4n+2] π Electrons: Syntheses, Structural Analyses,
Chi-Shin Wang1, Yu-Chen Wei2, Kai-Hsin Chang2
1Department of Chemistry, National Cheng Kung University, 70101, Tainan, Taiwan.
Abstract:
Indeno[1,2-b]fluorene-based [2,2]cyclophanes with 4n/4n and 4n/[4n+2] π-electron systems were prepared, and their structures were identified by X-ray crystallography. With short π-π distances around 3.0 Å, [2.2](5,11)indeno[1,2-b]fluorenophane and its precursor [2.2](5,11)indeno[1,2-b]fluorene-6,12-dionophane exhibit remarkable transannular interactions, leading to their unusual electrochemical and photophysical properties. With the aid of femtosecond transient absorption spectroscopy, the transition from the monomeric excited state to the redshifted H-type dimeric state was first observed, correlating to the calculated excitonic energy splitting and the steady-state absorption spectra induced by charge-transfer-mediated superexchange interaction.
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