Anthracene Cu(I) compounds with fluorescence and two-photon absorption properties

Abstract

A new ligand (L), 2-(2,3,6,7-tetramethoxy-9-(pyridin-2-yl)-9,10-dihydroanthracen-10-yl) pyridine, has been designed and synthesized. The anthracene ring in the ligand is curved and cannot form a large π bond conjugated system. Ligands have no fluorescence or other optical properties. When the ligand reacts with cuprous nitrate (CuNO3) to form complex (1), [LCuNO3], the anthracene ring magically straightens, and the maximum deviation of all the atoms on the anthracene ring from the anthracene ring plane is only 0.05873 Å. Complex (1) has a large two-photon absorption cross-sectional area and strong fluorescence properties. The nonlinear absorption of complex (1) (in DMF) was measured by the open-aperture Z-scan technique at a 532 nm wavelength. The results of Z-scan experiments show that complex (1) has remarkable nonlinear optical absorption effects with the two-photon absorption cross-section σ = 5969.78 GM. The ligand (L) and complex (1) all have certain thermal stability and their melting points are 169 °C for (L), and 297 °C for (1), respectively. Their properties indicate that they have potential applications.