Extended shortwave infrared absorbing antiaromatic fluorenium-indolizine chromophores
William E. Meador, Matthew A. Saucier, Max R. Tucker, Nicholas A. Kruse, Alexander J. Mobley, Connor R. Brower, Sean Parkin, Kensha Marie Clark, Nathan I. Hammer, Gregory S. Tschumper, Jared H. Delcamp
Abstract
absorption spectroscopy in 17 solvents, cyclic voltammetry, solution photostability, and transient absorption spectroscopy. Molecular orbital energies, predicted electronic transitions, and antiaromaticity are compared to higher energy absorbing chromophores using density functional theory. The presence of thermally accessible diradical states is demonstrated using density functional theory and EPR spectroscopy, while XRD crystallography confirms structural connectivity and existence as a single molecule. Overall, the FluIndz chromophore scaffold exhibits a rational means to access organic chromophores with extremely narrow optical gaps.