自组装,动力学和相变化动力学的捐赠-接受器替代烯衍生物
Nikos Tasios1, Christos Grigoriadis, Michael Ryan Hansen
1Department of Physics, University of Ioannina, 451 10 Ioannina, Greece.
Journal of the American Chemical Society
|May 8, 2010
概括
在perylenemonoimides中分支基链诱导有序的螺旋结构. 分子动力学揭示了冷核在有序阶段,但温度依赖的动力学在同otropic阶段,受链长度的影响.
科学领域:
- 材料科学 材料科学 材料科学
- 超分子化学 超分子化学
- 有机电子 有机电子
背景情况:
- 烯一模化物 (PMI) 是具有捐赠体-接受体特征的功能性有机材料.
- 基链替代是调整有机分子自我组装和性能的关键策略.
- 了解相位形成和分子动态对于设计先进的功能材料至关重要.
研究的目的:
- 研究基链替代对乙烯胺功能化PMI的相位行为的影响.
- 阐明分子包装,核心动力学和相变换机制.
- 使用各种光谱和散射技术,将分子结构与宏观性质相关联.
主要方法:
- 用于自组装相的结构分析的X射线散射.
- 热量计用于研究相位转换和热性质.
- 特定于特定地点的固态核磁共振 (NMR) 谱学用于分子动力学.
- 介电光谱检测受分子二极体影响的动力学.
主要成果:
- 排序的螺旋堆叠阶段仅在具有分支基链的PMI中观察到,具有60度的分子扭曲.
- 分子内键被确定为在有序阶段内柱内包装的稳定因子.
- 发现分子核心动态在有序阶段被结,但在同位素阶段表现出强烈的温度依赖,受链长度的影响.
结论:
- 分支基链对于在这些PMI中诱导有序的螺旋自组装至关重要.
- 链结构,键和分子包装之间的相互作用决定了相位形成和动态.
- 阶段转换动力学受到核化障碍的控制,同位素阶段动力学对链长度敏感.
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