Tuning the NIR Absorption Properties of 1,3,4,6,9b‐Pentaazaphenalene Derivatives Through the Spatially Separated Frontier Molecular Orbitals
Hiroyuki Watanabe, Junki Ochi, Kazuo Tanaka, Yoshiki Chujo
Abstract
Strategical modulation of energy levels of molecular electronic orbitals and resulting near‐infrared (NIR) absorption properties of 2,5,7,9‐tetrasubstituted 1,3,4,6,9b‐pentaazaphenalene (5AP) derivatives are reported. Recent reports on NIR‐absorbing materials mainly rely on donor–acceptor electronic interactions or macrocyclic π‐conjugated systems. We achieved the narrow HOMO–LUMO gap based on spatially separated frontier molecular orbitals (FMOs) of 5APs. The FMOs of 5APs enabled us to selectively tune either their HOMO or LUMO by choosing the position of the substituent.
Topics & Concepts
Molecular orbitalChemistryHOMO/LUMOSubstituentConjugated systemAtomic orbitalAbsorption (acoustics)Computational chemistryAbsorption spectroscopyBand gapPhotochemistryChemical physicsStereochemistryMoleculeOrganic chemistryOptoelectronicsMaterials sciencePhysicsOpticsElectronQuantum mechanicsPolymerLuminescence and Fluorescent MaterialsOrganic Electronics and PhotovoltaicsConducting polymers and applications