伦敦分散的上下文依赖的意义
Louis-Albin Gravillier1, Scott L Cockroft1
1EaStCHEM School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, U.K.
Accounts of chemical research
|November 23, 2023
概括
伦敦分散力是弱的和上下文依赖的,经常被溶剂效应和分子识别中的其他相互作用所掩盖. 它们的意义因系统,溶剂和距离而异.
科学领域:
- 物理化学 物理化学
- 超分子化学 超分子化学
- 化学物理 化学物理
背景情况:
- 伦敦分散力是范德瓦尔斯相互作用的关键组成部分,由原子中的短暂二极体产生的.
- 调查这些力量,特别是在解决方案中,是具有挑战性的,因为它们的弱和竞争性质.
- 溶解能量和溶解恐惧效应显著影响分子识别平衡和动力学.
研究的目的:
- 阐明伦敦分散力在分子识别中的上下文依赖意义.
- 将实验结果与现有关于分散力贡献的研究进行对比.
- 探索系统和溶剂的选择如何影响分散力的作用.
主要方法:
- 利用分子平衡,特别是分子内方法,以实验性地测量分散相互作用.
- 选了各种溶剂,以评估它们对分散力测量的影响.
- 分析了实验数据,并结合了对硬质障碍和应变最小化的理论考虑.
主要成果:
- 功能组之间的分散相互作用通常很弱 (<5 kJ mol-1),通常是静电和溶效应的次要影响.
- 与溶剂的竞争性分散相互作用受到溶剂批量极化性的影响.
- 分散力高度依赖于距离,导致特定环境的结果,并警告不要仅仅将稳定性归因于分散.
结论:
- 伦敦分散力的明显作用高度依赖于特定的分子系统和周围的溶剂环境.
- 防溶剂效应和溶剂的凝聚性能量密度可以稳定体积大的群体接触.
- 在解释分散力的贡献时,仔细考虑固体效应,应变和溶剂相互作用至关重要.
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