The role of aromatic π-bridges in push-pull-chromophores on the transparency-hyperpolarizability tradeoff

► Choice of aromatic bridge coupled with the substitution pattern on the ring allows targeting specific spectral features (absorption or transparency windows). ► Asymmetric bridges (e.g., azulene) produce large hyperpolarizabilities. ► Zwitter-ionic mesomers rationalize hyperpolarizability and spectral trends.