Novel nonlinearity–transparency–thermal stability trade-off of thiazolylazopyrimidine chromophores for nonlinear optical application

Novel, nonlinear optical thiazolylazopyrimidine chromophores were synthesized and characterized by UV–vis spectroscopy, hyper-Rayleigh light scattering and thermogravimetric analysis. The thiazolylazopyrimidine chromophores exhibited large molecular hyperpolarizabilities which were larger than that of a chromophore derived from 4-nitroaniline, owing to the presence of the electron-deficient thiazole ring at the acceptor end of the molecule. Moreover, in comparison with an analogous aniline based chromophore, the thiazolylazopyrimidine chromophores displayed a large blue shift due to the presence of the electron-poor pyrimidine ring at the donor end molecule, resulting in an improvement in optical transparency. The thiazolylazopyrimidine chromophores displayed high thermal stability owing to the presence of the thiazole and pyrimidine rings. Such novel, nonlinear optical thiazolylazopyrimidine chromophores are distinguished by good nonlinearity–transparency–thermal stability trade-off for nonlinear optical application.