中文摘要：

设计并合成了-系列含不同末端给电子基团及共轭链长度的1，1-二腈基．2，2-二苯基乙烯类化合物（D1-D7），用核磁共振氢谱（1HNMR）、核磁共振碳谱（13CNMR）和高分辨质谱（HRMS）对分子结构进行了表征．选用N，N-二甲基甲酰胺（DMF）为溶剂，测定了它们的线性光物理性质，用光漂白法研究了它们的光稳定性，用热失重法测试了它们的热稳定性．研究了这7个化合物针对800nm脉冲激光（掺钛蓝宝石激光器，脉冲宽度～130fs，重复频率1000Hz）的光限幅性质．结果表明：以二烷基氨基为给电子基团的4个化合物（D4-D7）对800nm的飞秒脉冲激光均具有显著的光限幅性能，限幅机制为双光子吸收（2PA），而端基给电子能力较弱、共轭链长较短的D1-D3光限幅效果并不明显．此外，D4-D7都具有较好的热稳定性和光稳定性．而且，该系列化合物的双光子吸收截面、光稳定性和热稳定性都具有随分子结构中给电子基团增强或共轭链增长而增大或提高的趋势．D7具有最好的综合性能，是-个有应用潜力的光限幅材料．

英文摘要：

A series of malononitrile derivatives （D1-DT） with different electron donors and conjugation lengths were designed and synthesized. Their structures were characterized using 1H and 13C nuclear magnetic resonance （NMR） spectroscopies, and high-resolution mass spectrometry （HRMS）. Their linear photophysical properties were investigated in dimethylformamide （DMF） solutions, their optical stabilities were investigated using photobleaching experiments, and their thermal stabilities were determined using thermogravimetric analysis （TGA）. The optical limiting behaviors of D1-D7 under an 800 nm femtosecond pulsed laser （Ti：sapphire laser, ~130 fs, 1000 Hz） were investigated. The results showed that four of the compounds （D4-DT）, which had dialkylamines as electron donors, exhibited significant optical limiting behaviors, based on two-photon absorption （2PA）, but the other three compounds （D1-D3）, which had either weak donors or short conjugation lengths, showed very weak optical limiting behaviors. All the compounds had good photochemical and thermal stabilities. The 2PA cross-sections and optothermal stabilities of this series of compounds increased with increasing conjugation length or electron-donating ability of the alkylamine groups in their structures. D7, which had the best properties, is a potential candidate for optical limiting applications under an 800 nm femtosecond pulsed laser.