通过盘状分子在固体-液体界面的自我组装而形成的超分子阶梯
P Samorí1, A Fechtenkötter, F Jäckel
1Department of Physics, Humboldt University Berlin, Invalidenstrasse 110, 10115 Berlin, Germany.
Journal of the American Chemical Society
|November 15, 2001
概括
赫克萨本佐可罗 (HBC) 衍生物在石墨上自组成有序的二维数组. 烯间隔器和奇拉侧链的存在影响了扫描道显微镜 (STM) 成像中的分子排列和对比度.
科学领域:
- 超分子化学 超分子化学
- 材料科学是一种材料科学.
- 表面科学是一门科学.
背景情况:
- 六enzocoronenes (HBCs) 是以自我组装成有序结构而闻名的光盘分子.
- 控制接口上的分子排列对于开发先进材料至关重要.
- 侧链性和分子架构对自我组装的影响是一个活跃的研究领域.
研究的目的:
- 为了研究可溶性HBC衍生物的自组装行为,具有不同的侧链和烯间隔器.
- 了解分子结构,包括性,如何影响HBC单层在高度导向的烧解石墨 (HOPG) 上的排序和电子特性.
- 探索创建具有可调节性质的新型超分子架构的潜力.
主要方法:
- 合成具有光学活性和racemic侧链的可溶性HBC衍生物,带有或没有烯间隔器.
- 在溶液-石墨界面上组装HBC衍生物.
- 分子分辨率扫描道显微镜 (STM) 来成像自组装的单层.
- 对STM对比差异的分析,以推断分子构造和排列.
主要成果:
- 所有研究的HBC衍生品都在HOPG上自组装成准2D定向的晶体阵列.
- 具有烯间隔器的HBC表现出单层中芳香核的不同STM对比度,与简单的基替代HBC不同.
- 光学活性基替代HBCs形成一个有规律的超结构,具有三个不同的分子位置,类似于楼梯.
- 种族性HBC衍生物显示出对比的随机分布,而光学活跃的呈现出周期性安排.
结论:
- 烯间隔器破坏了分子平面性,导致表面的不同形状和不同的平衡位置.
- 侧链的性在决定自组装超结构的周期性和顺序方面发挥着至关重要的作用.
- 观察到的自我组装是由内部,内部和界面相互作用的复杂相互作用所支配的.
- 这些发现为使用扫描道光谱 (STS) 和潜在的STM尖端诱导分子切换研究分子-基板合的可能性提供了新的可能性.
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