Two novel terpyridine-based chromophores with donor-acceptor structural model containing modified triphenylamine moiety: Synthesis, crystal structures and two-photon absorption properties

Two novel terpyridine-based chromophores with D-A (D = donor, A = acceptor) structural model containing modified triphenylamine moiety (L 1 and L 2 ) have been conveniently synthesized via formylation and reduction in satisfactory yields, and fully characterized. The single crystals of them were obtained and determined by X-ray diffraction analysis. The relationships between structure and photophysical properties of the two chromophores were investigated both experimentally and theoretically. The measured maximum TPA cross-sections per molecular weight (δ max/MW) of the chromophores are 0.63 GM/(g mol) (L 1 ) and 0.72 GM/(g mol) (L 2 ), respectively, in DMF as a high polar solvent. The results indicate that the value of δ max/MW could be well tuned by the intramolecular charge transfer (ICT), which could be realized by introducing additional electron-donor/acceptor groups.