A series of D-π-A chromophores based on [1,2,5]oxadiazolo[3,4-b]pyrazine electron-withdrawing group has been designed. The influence of the π-conjugated linker (1,4-phenylene and 2,5-thienylene) and the amino-electron-donating group (diphenylamino and carbazol-9-yl) was studied by cyclic voltammetry, UV-Vis and emission spectroscopy. The second order nonlinear optical properties were also studied using the electric field induced second harmonic generation (EFISH) method. The experimental results have been rationalized by theoretical DFT calculations.

中文翻译：

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[1,2,5]恶二唑并[3,4- b ]吡嗪基线性推挽系统的合成，光物理和非线性光学性质

设计了一系列基于[1,2,5]恶二唑并[3,4- b ]吡嗪吸电子基团的D-π-A发色团。通过循环伏安法，紫外-可见光谱和发射光谱研究了π共轭连接基（1,4-亚苯基和2,5-亚噻吩基）和氨基给电子基团（二苯基氨基和咔唑-9-基）的影响。 。还使用电场感应二次谐波产生（EFISH）方法研究了二阶非线性光学性质。实验结果已经通过理论DFT计算得到了合理化。