Synthesis, Characterization, and Photophysical Properties of a New Indolizine Pyridine Complex with a Large Two-Photon Absorption Cross-Section

The value of two-photon absorption cross-section represents the effectiveness of simultaneous absorption of two incident photons. We reported a novel organic TPA material which has not reported before. It is an acceptor-pi-donor-pi-acceptor (A-pi-D-pi-A) idolizing pyridine compound 1, namely 3-(pyridin-2-yl)-N-(3-(pyridin-2-yl)indolizin-1-yl)indolizin-1-aminium perchlorate, (C26H20N5)center dot ClO4. The material can be easily synthesized in a one-pot method with cheap materials. The compound 1 was structurally characterized through single-crystal X-ray crystallography, Hirshfeld surface, and spectroscopic techniques. Its photophysical properties were investigated. Compound 1 gives blue fluorescence and the lifetime of the emission peak in ethanol solution is tau=0.607 ns. The nonlinear absorption of the compound 1 solutions (in C2H5OH) was measured by the open-aperture Z-scan technique at a 532 nm wavelength. The results of Z-scan experiments show that compound 1 has remarkable nonlinear optical absorption effects. The TPA cross-section is delta=22583 GM.