SYNTHESIS AND NONLINEAR-OPTICAL PROPERTIES OF DONOR-ACCEPTOR-SUBSTITUTED TRIARYL AZOLE DERIVATIVES

A variety of optically nonlinear chromophores containing a five-member ed imidazole, oxazole, or thiazole ring have been prepared and charact erized. These consist of 2,4,5-triphenyl-substituted azole heterocycli c systems in which the 2-aryl ring bears an electron-withdrawing subst ituent and the 4,5-aryl rings bear an electron-donating substituent. A dditionally, some planar analogues, phenanthro[9,10-d]imidazoles, were also prepared and evaluated. The utility of these chromophores will b e dictated by their linear absorption wavelength and oscillator streng th, microscopic optical nonlinearity, ground-state dipole moment, ther mal stability, and solubility. The tradeoffs between these structure-d ependent properties are discussed with regard to exploitation of these chromophores as guest dyes in high-temperature thermoplastics.