Extended π-conjugated quinazolinone derivatives with enhanced third-order nonlinear optical response

Abstract

A series of quinazolinone derivatives have been designed and synthesized based to the structure of donor-π-acceptor-π-donor (D-π-A-π-D). In order to obtain materials with good third-order nonlinear optical response that we have introduced some electron-donating groups such as triarylamine, cumene, and N,N-dimethylaniline into the 8- or 2,8- position of the quinazolinone. Compared with the parent QZ-1, the target compounds showed a significant red shift. Electrochemical data and theoretical calculation showed that the introduction of the donor group that extended the conjugation length of the molecule and reduced the HOMO/LOMO band gap which promoted the intramolecular charge transfer (ICT). Z-scan results demonstrated that as the electron-donating ability of the donor group increased, the synthetic materials exhibit stronger nonlinear optical response. Among them, QZB-1 incorporating with two triarylamine groups has a γ value of 34.616 × 10−32 esu, which is up to 38 times of the parent structure. The results of this study have guiding significance for the molecular design of nonlinear optical materials.