与结合的离子对复合体的稳定性随着溶剂极性增加而意外增加
Debashree Manna1, Rabindranath Lo1, Jaroslav Vacek1,2,3
1Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo námĕstí 542/2, 160 00, Prague, Czech Republic.
Angewandte Chemie (International ed. in English)
|March 18, 2024
概括
与常见假设相反,离子对键的稳定性随着溶剂极性而意外增加. 这项研究揭示了影响溶液中的分子复合体稳定性的电荷转移动态.
科学领域:
- 物理化学 物理化学
- 计算化学计算化学
- 超分子化学 超分子化学
背景情况:
- 传统上,假设离子对与结合的复合体稳定性随着溶剂极性增加而下降.
- 这种假设是基于与溶剂可访问表面积 (SASA) 相关的静电能降低和溶解效应.
研究的目的:
- 为了研究溶剂极性的影响,对稳定性离子对结合的复合物.
- 挑战对分子复合体稳定性溶解效应的传统理解.
主要方法:
- 结合了实验技术:核磁共振 (NMR) 和红外光谱.
- 采用计算方法:量子化学计算和分子动力学 (MD) 模拟.
主要成果:
- 显示,随着溶剂极性增加,2- propionic 酸和n-丁胺复合物的结合自由能量增加.
- 确定综合体子系统之间的实质性电荷转移是关键的稳定因素.
结论:
- 质疑了关于极性溶剂中离子对键稳定性下降的一般假设.
- 溶解动态更复杂,涉及大量的电荷转移,可以提高极地环境的稳定性.
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