六个不同的组件从一个构建块:二维结晶的胺两的两维结晶
1Department of Chemistry and the Macromolecular Science and Engineering Program, University of Michigan, Ann Arbor, Michigan 48109-1055, USA.
Journal of the American Chemical Society
|August 12, 2010
概括
这项研究揭示,一个C(s) -对称的胺两体形成了多个结晶相,在接口上有纳米级的空隙. 这些多样化的固体形式来自于非共价相互作用和动力/热力学因素,影响结晶.
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.
- 结晶科学是结晶的科学.
背景情况:
- 两类分子是具有水友性和疏水性部分的分子.
- 两动物可以自组装成各种结构.
- 了解自我组装对于设计新材料至关重要.
研究的目的:
- 为了研究液体/固体界面上由C(s) -对称的胺双体形成的晶体相.
- 分析这些结晶相的多样性的结构基础.
- 了解非共价相互作用和结晶动力学/热力学在相位形成中的作用.
主要方法:
- 合成一个C(s) -对称的胺二烯基与一个C(18) 链.
- 使用像X射线衍射和显微镜 (隐含) 这样的技术来表征晶相.
- 分析每个阶段内的分子包装和分子间相互作用.
主要成果:
- 在液体/固体界面观察到至少六种不同的晶体相.
- 几个阶段呈现出定期排列的纳米层空洞.
- 复杂和对称的图案是通过各种聚合物形成的,这些聚合物通过非共价相互作用稳定,特别是从初级胺中形成的键.
- 阶段形成受到动力和热力学因素的影响,一些阶段表现出度依赖的稳定性.
结论:
- 这项研究表明,对于单一的两动物来说,固体形式的多样性是显著的.
- 非共价相互作用,特别是键,是自我组装和模式形成的关键驱动因素.
- 动力和热力学控制都会影响得到的晶体结构.
- 这些发现有助于理解二维和三维结晶以及固体形式的多样性.
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