Characterization of Push-Pull Polyenes of Increasing Size: Linear and Quadratic Polarizabilities in Solution

Push-pull molecules have been extensively studied for their properties in the field of quadratic nonlinear optics. Such molecules consist of electron-donor and electron acceptor substituents connected via a conjugation path. The partial intramolecular charge transfer (ICT) between these end groups can lead to large ground-state dipoles μ. Also, they can display huge static quadratic hyperpolarizabilities β(0) related to the occurence of the ICT transition between the ground and first-excited states [1].