New Idea for Narrowing an Energy Gap by Selective Perturbation of One Frontier Molecular Orbital

In this manuscript, we will illustrate a new idea for narrowing energy gaps between frontier molecular orbitals (FMOs) by selectively perturbing the levels of highest occupied (HOMOs) and/or lowest unoccupied (LUMOs). Initially, basic concept isolated FMOs is explained employing pentaazaphenalene (5AP) derivatives. It was found that electronic structures LUMO 5AP can be preserved even when incorporated into polymer chains if connecting points are separated from LUMO. The mechanism and their unique properties summarized. Next, conversely, HOMO perturbed conjugation effects independently. On basis fact, near infrared (NIR)-absorbing molecules obtained elevating lowering levels. We also mention strategies enhancing luminescent Finally, demonstrate in commodity dyes, such as boron dipyrromethene (BODIPY). By level through aza-substitution at skeletal carbon where distributed, NIR-emissive polymers obtained. Versatility obtaining optoelectronic organic materials review.