The Synthesis And Study Of Novel Two-Photon Absorption Materials

After M.Goppert-Mayer theoretical propose a process of simultaneously absorb two long wavelength photon could also achieved the transition from ground state to excited state in 1931 and Kaser and Garrett experimentally improved it 30 years later, a new scientific area aroused which mainly studied two-photon absorption(TPA) and multi-photon absorption. Due to the potential application in light limiting, 3D fabrication, 3D storage and two-photon microscopy by their nonlinear optical properties, researchers are exploring new molecules with large two-photon absorption cross section which mainly affected by the molecule structure such as conjugated length, planarity,the functional group, symmetry and so on.Due to 1,4-Diketo-3,6-diphenylpyrrolo[3, 4-c]pyrrole (DPP) and its derivatives represent a class of brilliant red and strongly ?uorescent high performance pigments that have exceptional light, weather and heat stability, and a high light fastness, they were reported by many researchers with the demonstration of high performance in opto-electrical devices. In this work, we connect electron-donating diphenylamine and triphenylamine groups to the 3, 6-positions of electron-withdrawing pyrrolo[3, 4-c]pyrrole-1, 4-dione via 1, 4-phenylene conjugation bridges to form novel D-π-A-π-D-type TPA dyes (DPP-DPA and DPP-TPA). The results show that these DPP-based conjugated molecules exhibit large TPA cross-sections: DPP-DPA (δmaxTPA=1200GM,Φ=0.37), DPP-DPA (δmaxTPA=930GM,Φ=0.46).With the emergency of cross-linked conjugated materials, they have greatly widened the scope of molecular candidates applicable in molecular sensors, switches, nonlinear optical-materials, organic field effect transistors, photoluminescence and electroluminescence. Among them, donor/acceptor-functionalized cross-shaped chromophores, namely, cruciforms, have been the subject of considerable study due to their unique and interesting optoelectronic properties. In the current work, we employ new synthetic routes to prepare two new donor-acceptor substituted anthracene- centered cruciforms CDAE (δmaxTPA=2670GM)and CDAV(δmaxTPA=2570GM), and two new linear analogues B26A (δmaxTPA=470GM) and B910V (δmaxTPA=160GM). Furthermore, their one- and two-photon properties and FMO properties are investigated. For the sake of comparison, the corresponding tetra-donor cruciforms which have been reported in previous works, C4DE and C4DV, and another two linear analogues, 9, 10-bis (p-didecylaminophenylethynyl) anthracene (B910E) and 2, 6-bis (p-dihexylaminostyryl) anthracene (B26D), are also included. The result showed the emission of the cruciforms are all redshift and the TPA absorption cross section enhanced compared with the corresponding linear analogues, which is different with our familiar benzne centered cruciforms that without enhancement absorption. The FMO and solvatochromic behaviors reveal that donor-acceptor substituted anthracene-centered cruciforms show spatially separated HOMOand LUMO, which has potential application in two-photon sensors.