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

Abstract 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‐π‐donor‐π‐acceptor (A‐π‐D‐π‐A) idolizing pyridine compound 1 , namely 3‐(pyridin‐2‐yl)‐N‐(3‐(pyridin‐2‐yl)indolizin‐1‐yl)indolizin‐1‐aminium perchlorate, (C 26 H 20 N 5 )⋅ClO 4 . 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 τ=0.607 ns. The nonlinear absorption of the compound 1 solutions (in C 2 H 5 OH) 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 δ=22583 GM.