Structure–property relationships in a new series of two-photon absorbing D–π–D divinyl-biphenyl derivatives

The study on the structure–property relationships of divinyl-biphenyl derivatives demonstrates the following results: Changing the charge transfer dipoles only by substituting the terminal donor group, the two-photon absorption cross-sections of these molecules range from 9.1 to 745 GM, while the emission peak remains in blue region and the quantum yield vary slightly. As the intra-molecular charge transfer dipole larger than a value the symmetrical π-system will rotate around the center single bond, and it will decrease their complanarity of π-conjugated plane, which limits the further enhancement of two-photon absorption cross-section, together with the quantum efficiency decrease.