伦敦分散有助于精细化体A值:分散能量供应量表
Ephrath Solel1, Marcel Ruth1, Peter R Schreiner1
1Institute of Organic Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, 35392 Giessen, Germany.
Journal of the American Chemical Society
|November 30, 2021
概括
一个新的尺度量化了分散能量捐赠者 (DED),使得直接与硬质效应进行比较. 这种尺度显示伦敦分散相互作用显著影响着形状偏好,挑战了先前的假设.
科学领域:
- 计算化学
- 分子建模
- 有机化学
背景情况:
- 传统上,替代环素的形状偏好归因于硬质因素.
- 通常用于评估体体积的A值被重新评估,以包括非体相互作用.
研究的目的:
- 为分散能量捐赠者 (DED) 开发一个定量尺度,以便直接与硬质效应进行比较.
- 研究伦敦分散 (LD) 相互作用在单替代环素的结构偏好中的作用.
主要方法:
- 使用单替代环素的计算研究.
- 根据修改的A值开发了一个DED尺度.
- 为量化比较创建了一个补充的标准尺度.
主要成果:
- 确定伦敦散射相互作用与硬质障碍一起对形状偏好有重大贡献.
- 新的DED尺度允许在分散和固态相互作用之间进行直接的定量比较.
- 在解释复杂的相对群体大小数据方面证明了LD相互作用的实用性.
结论:
- A值包括固态和有吸引力的伦敦分散相互作用.
- 伦敦分散是决定分子构成的一个关键因素,但常常被低估.
- 开发的尺度为分析相互竞争的分子间力量提供了一个新的框架.
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