迪拉基特征对二光子吸收的影响:由艾伦基前体合成的 bis (((acridine) 模态
Kenji Kamada1, Shin-ichi Fuku-en, Shu Minamide
1National Institute of Advanced Industrial Science and Technology (AIST), Ikeda, Osaka 563-8577, Japan. k.kamada@aist.go.jp
Journal of the American Chemical Society
|December 11, 2012
概括
与封闭外对应物相比,单片二基二 () 模具有超过100倍的增强的两光子吸收 (TPA). 这突显了激进性特征在提高TPA强度方面的潜力.
科学领域:
- 光化学和光物理学
- 有机化学 有机化学
- 材料科学 材料科学 材料科学
背景情况:
- 两光子吸收 (TPA) 是一个重要的光物理过程,在3D成像和材料科学中具有应用.
- 分子结构,二根性质和TPA特性之间的关系是一个活跃的研究领域.
- 之前的研究表明,中间二根性质可以增强TPA,但直接比较是有限的.
研究的目的:
- 合成和表征一个具有显著单个二基性质的 bis ((acridine) 二元体.
- 为了比较这个二基二聚体的TPA特性与其封闭外对应物.
- 调查激进性对TPA截面的影响.
主要方法:
- 通过双氧化一个艾伦基前体,合成一个 bis (((acridine) 四离子二聚体 (8).
- 使用X射线分析进行结构性表征.
- 计算分析 (ab initio分子轨道计算) 来确定二根性质 (y).
- 在溶液和固体状态下进行光谱测量 (一光子和两光子吸收).
- 电化学氧化/还原用于在二基和封闭物种之间进行交互转换.
主要成果:
- 合成了 bis ((acridine) 二聚体 (8),并证实它具有很高的共平面性和结合性.
- 基态计算表明,二次元8.8的中间二次元 (y=0.685) 是一个二次元.
- 与其封闭外模拟器 (12,<21GM) 相比,Dimer 8的TPA截面显著增强 (3600GM在1200nm).
- 通过氧化还原过程,二根基四离子二聚体 (8) 可以与其闭二离子对应物 (12) 进行可逆互转.
结论:
- 这项研究提供了一个直接的实验比较,对具有相同的骨架,但具有不同激进性质的分子之间的TPA活性进行比较.
- 这些结果强烈支持理论预测,即中间激进特征增强TPA强度.
- 这项工作展示了为先进的光子应用设计二极端有机分子的潜力.
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