线性和纹带的热力学稳定性和在胺 - 酸盐组件中的循环罗塞特:一个模型描述
A G Bielejewska1, C E Marjo, L J Prins
1Laboratory of Supramolecular Chemistry and Technology, MESA(+) Research Institute, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands.
Journal of the American Chemical Society
|August 2, 2001
概括
模型计算显示,自组装成磁带或粉圈对粉圈内部能量参数非常敏感,而不是磁带的稳定性. 调整平衡常数和相互作用参数会显著影响带/粉丝圈比率,在特定条件下,粉丝圈更受欢迎.
科学领域:
- 超分子化学 超分子化学
- 化学物理 化学物理
- 材料科学 材料科学 材料科学
背景情况:
- N,N-非替代的胺和N-替代的酸或巴比酸衍生物的自我组装是由键驱动的.
- 这些分子可以形成线性/纹带或循环.
研究的目的:
- 为了建模这些衍生品的自组装过程,使其成为磁带和红带.
- 为了研究影响带与罗塞特结构的比率的因素.
主要方法:
- 开发了一个模型,考虑了所有立体异构体带结构 (270个物种) 和一个状结构.
- 整合了八个表态参数,表示组件内部的相互作用.
- 分析了磁带/红带比率对平衡常数和硬质参数变化的灵敏度.
主要成果:
- 带/带比对影响带内部能量的参数非常敏感,例如平衡常数 (K(0),K(r)) 和胺-酸相互作用 (R(12) -a(Z) (b).
- 增加K(0) 或K(r) 显著有利于罗塞特形成.
- 仅影响带内部能量 (R(13) -R(28) 的参数对带/红带比率的影响最小.
- 模型预测与外围拥挤概念形成鲜明对比,这表明重的替代剂可能会增加带的溶解度.
结论:
- 自组装平衡主要是由影响罗塞特稳定性的因素决定的.
- 许多可能的带结构起到了缓冲作用,稳定了整体平衡.
- 需要对带和带结构的硬质效应进行进一步的研究,这可能解释实验观察结果.
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