Replacing carbazole with [2.2]paracyclophane and triptycene donors: theoretical insights into the modulation of second-order nonlinear optical properties

Through-space interactions in [2.2]paracyclophane and triptycene-based carbazole donors enhance intramolecular charge transfer, boosting the static first hyperpolarizability ( β tot ) of these D–π–A NLO materials.