Synthesis and characterization of thiazole-containing chromophores for second-order nonlinear optics

Abstract

Push-pull thiazole-containing nonlinear optical chromophores with dicyanovinyl and tricyanovinyl acceptors, along with their thiophene analogs, have been synthesized and characterized. The onset temperatures of thermal decomposition of these chromophores determined by DSC are above 240 °C. The redox properties of the chromophores were studied by cyclic voltammetry and the results reveal the electron-deficient (thiazole) and electron-excessive (thiophene) nature of the heterocycles. Experimental measurements of second-order nonlinear optical response (µ·β) indicate that the combination of either a thiazole or thiophene conjugating unit and a tricyanovinyl acceptor results in a nonlinear optical chromophore exhibiting substantial molecular hyperpolarizability (µ·βca. 7000×10^–48 cm⁶ at 1907 nm).

References

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