Synthesis and comparative studies of coumarin-based nonlinear optical chromophores with different conjugated electron bridge

Two novel nonlinear optical (NLO) chromophores JC-T-TCF and JC-F-TCF utilizing tetramethyljulolidine-based coumarin and tricyanofuran(TCF) as the electron donor and acceptor, respectively, were designed and synthesized. The two chromophores were linked with different pi conjugated electron bridge (thiophene group and furan group), which provide the opportunity to study the structure-property relationship of coumarin-based chromophores. Both the novel obtained chromophores exhibited reasonable stability and solvatochromic effect. The theoretical calculation results indicated that both chromophores possess microscopic hyperpolarizability (beta) in excess of 320 x 10(-30)esu, and the chromophore JC-T-TCF utilizing thiophene group as the electron bridge exhibited obviously larger beta value (456.8 x 10(-30)esu). The larger beta value, combination with the larger mu value, endowed JC-T-TCF with larger electro-optic activity of 70 pm V-1 at the wavelength of 1310 nm in the guest-host films of chromophores doped into PMMA, which provide the potential application opportunity in the field of optical waveguide devices.