键强度对酸盐合作性的影响
Christopher A Hunter1, Maria Cristina Misuraca, Simon M Turega
1Department of Chemistry, University of Sheffield, Sheffield S3 7HF, United Kingdom. c.hunter@sheffield.ac.uk
Journal of the American Chemical Society
|November 25, 2011
概括
这项研究量化了超分子架构中的分子内键. 较强的键,如酸二-,比较弱的-键更有助于复杂的稳定性.
科学领域:
- 超分子化学 超分子化学
- 物理有机化学 有机化学
- 化学热力学化学热力学
背景情况:
- 金属氨酸-连接体复合物被用来探测非共价相互作用.
- 内分子键显著影响了超分子组合和稳定性.
- 了解不同键强度的能量贡献对于设计新型分子架构至关重要.
研究的目的:
- 在24个不同的超分子架构中量化分子内以太--键的自由能量贡献.
- 在相同的分子框架内比较弱 (乙 - ) 和强 (酸 - ) 键的特性.
- 确定分子内相互作用的有效度 (EM) 并评估它们对复合体稳定性的影响.
主要方法:
- 在中利用化学双变异周期来测量自由能量贡献.
- 分析复合体作为部分结合状态的集合,以确定有效的度.
- 在相关联联体系统中比较了以太-相互作用与酸盐二-相互作用.
主要成果:
- 乙醇-相互作用较弱,部分结合状态的大量种群存在.
- 酸二-相互作用更强,在24种结构中23种结构中导致了分子内H键.
- 只有8个架构显示了可检测的-相互作用的H键,表明强度不足以克服重组成本 (KEM < 1).
- 有效度 (EM) 值在不同的H键受体之间线性相关,这表明EM是结构依赖的.
- 在同一个框架下,酸二H键的绝对EM值比以太-H键低约4倍.
结论:
- 分子内键的强度决定了它们对超分子稳定性的贡献.
- 超分子架构影响了键的有效度和能量贡献.
- 观察到的差异突出显示了键强度,有效度和整体复杂稳定性之间的相互作用.
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