Two benzothiazolium salts of D-π-A structure, (E)-3-ethyl-2-(2-(pyren-1-yl) vinyl) benzo[d]thiazol-3-ium iodide (EPBI) and (E)-3-ethyl-2-(2-(9-ethyl-9H-carbazol-3-yl) vinyl) benzo[d]thiazol-3-ium iodide (ECBI) were synthesized and spectroscopically characterized. Z-scan measurements were performed at 532 nm with 190 femtosecond and 15 picosecond laser beam respectively. EPBI displays the efficient third-order nonlinear optical susceptibility ${\chi }^{\left(3\right)}$ of 1.5 × 10⁻¹¹ esu and molecular second-order hyperpolarizability γ of 2.8 × 10⁻²⁹ esu which are one order larger than those of ECBI, and EPBI exhibits reverse saturable absorption and self-defocusing refraction while ECBI exhibits saturable absorption and self-focusing refraction in 15 ps time mechanisms. In 190 fs time mechanisms, both of them exhibits saturable absorption. Further dynamics analysis for these transition in different time regimes and determination of key parameters were performed via DFT calculation and transient absorption experiment.

两种D-π-A结构的苯并噻唑鎓盐，（E）-3-乙基-2-（2-（2-（吡喃-1-基）乙烯基）苯并[d]噻唑-3-碘化碘化物（EPBI）和（E）合成了-3-乙基-2-（2-（9-乙基-9H-咔唑-3-基）乙烯基）苯并[d]噻唑-3-碘化碘（ECBI），并对其进行了光谱表征。Z扫描测量分别在190 nm的190飞秒和15皮秒的激光束下于532 nm进行。EPBI显示有效的三阶非线性光学磁化率${\chi }^{（3）}$ 比ECBI高1.5×10 ^-11  esu和2.8×10 ^-29 esu的分子二阶超极化率γ ，EPBI表现出反向饱和吸收和自散焦折射，而ECBI表现出饱和吸收和自散焦。 15 ps时间机制的聚焦折射。在190 fs的时间机制中，它们都表现出饱和的吸收。通过DFT计算和瞬态吸收实验对这些在不同时间范围内的跃迁进行了进一步的动力学分析，并确定了关键参数。