对光敏感宏循环的亚分子观测及其对主机-客户网络的异构化效应
Yong-Tao Shen1, Li Guan, Xiao-Yang Zhu
1National Center for Nanoscience and Technology (NCNST), Beijing 100190, PR China.
Journal of the American Chemical Society
|April 16, 2009
概括
光敏感的宏循环矩形自组装成有序的数组,使用主机-客户模板. 紫外线诱导光异构化,改变客宿主网络,并通过STM观察到的独特的形状异构体.
科学领域:
- 超分子化学 超分子化学
- 摄影化学的使用.
- 材料科学 材料科学 材料科学
背景情况:
- 具有光敏感单元的宏环化合物正在探索模仿自然光调节功能的方法.
- 对分子阵列的控制组装对于开发先进的功能材料至关重要.
研究的目的:
- 用宿主-客分子模板演示光敏宏循环矩形的受控组装.
- 研究宏环分子的光异构化行为及其对自我组装的影响.
主要方法:
- 利用宿主-客分子模板来控制宏循环矩形的组装.
- 采用紫外线照射,诱导宏环分子的光异构化.
- 采用扫描道显微镜 (STM) 来观察和区分不同的形状异构体及其自组装的附加层.
主要成果:
- 实现了对光敏感宏循环矩形的有序数组的受控组装.
- 在紫外线照射下观察到4NN-宏循环分子从跨-跨-跨-跨 (t,t,t,t) 到各种异构体 (例如,t,t,t,c; t,c,t,c) 的光异构化.
- 证明光异构体显著影响客主网络特征.
- 显著的多重构造异构体 (t,t,t,t; t,t,t,c; t,c,t,c) 自组装成不同的附加层与TCDB在HOPG表面.
结论:
- 这项研究提供了一个简单的方法来研究宏循环结构内的阿佐基组的光异构化.
- 证明了控制光异构化宏循环的自我组装的能力,从而产生了不同的超分子架构.
- 突出了光异构化对分子自我组装和客宿主相互作用的影响.
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