1,3,5-tricyano-2,4,6-tris(styryl) 衍生物的两个光子吸收特性
1Molecular Opto-Electronics Laboratory, Department of Chemistry and Center for Electro- & Photo-Responsive Molecules, Korea University, 1-Anamdong, Seoul 136-701, Korea.
Journal of the American Chemical Society
|October 11, 2001
概括
研究人员研究了新型衍生物中的二光子吸收 (TPA). 他们发现,增加结合长度和供体强度可以增强TPA的特性,为设计新的TPA染料提供了一种策略.
科学领域:
- 非线性光学是非线性光学.
- 材料科学 材料科学 材料科学
- 有机化学 有机化学
背景情况:
- 两光子吸收 (TPA) 是一种非线性光学过程,在显微镜和光学数据存储中具有应用.
- 带有扩展pi-conjugation的烯衍生物是TPA材料的有希望的候选物.
研究的目的:
- 为了研究1,3,5-tricyano-2,4,6-tris(styryl) benzene衍生物的TPA特性.
- 了解分子结构和TPA效率之间的关系.
主要方法:
- 光谱分析包括一个光子的吸收,光和激发光谱.
- 使用纳米秒脉冲的两光子诱导光法测量TPA截面 (delta(max)).
主要成果:
- 化合物表现出较大的斯托克斯移位,随着结合长度的增加而增加.
- 一个和两个光子的激发光谱相似,表明共享激发状态.
- 峰值TPA截面值范围在 (50-2620) x 10(-50) cm4 s/光子之间.
- 随着捐赠者的强度和结合的长度,TPA的效率会增加.
结论:
- 在delta (最大) 和beta (超极化) 之间存在线性关系.
- 这种三角-β关系为设计新型八极性TPA染料提供了有价值的合成策略.
- 研究的化合物显示出TPA应用的巨大潜力.
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