用辅助溶剂调整宿主-客体封装的自由能量
Melinda Nolten1, Kay T Xia2,3, Simone Pezzotti1
1Department of Physical Chemistry II, Ruhr University Bochum, 44801 Bochum, Germany. martina.havenith@rub.de.
Physical chemistry chemical physics : PCCP
|April 30, 2025
概括
即使是微小的溶剂成分变化也会显著改变超分子纳米中的客体封装热力学. 这影响了热驱动力,这对于催化和分离应用至关重要.
科学领域:
- 超分子化学 超分子化学
- 物理化学 物理化学
- 化学物理 化学物理
背景情况:
- 超分子宿主提供可调节的微环境,通过硬体和静电效应进行反应.
- 水腔内的溶剂成型是纳米宿主中客体封装的关键热力学驱动因素.
研究的目的:
- 为了研究微小的溶剂成分变化对超分子纳米中客体封装自由能量的影响.
- 阐明溶剂对客体结合的影响的热力学和结构基础.
主要方法:
- 综合特拉赫兹 (THz) 光谱,核磁共振 (NMR) 和分子动力学 (MD) 模拟.
- 对封装的和变化的分析.
- 纳米腔内溶剂分子行为的表征.
主要成果:
- 仅仅5%的溶剂成分变化就会对封装的自由能量产生深刻的影响.
- 一个单个DMSO分子对纳米腔的优先占用大大降低了贡献 (ΔS) 从63-76 cal mol-1 K-1到23-24 cal mol-1 K-1.
- 由于DMSO分子占用而导致的腔体积减少解释了观察到的变化,独立于金属连接体顶点.
结论:
- 超分子宿主中客体结合的热驱动力对局部溶剂组成的微妙变化高度敏感.
- 纳米主体内的溶剂调节是调节催化效率的关键因素.
- 这些发现为超分子催化和通过精确的溶剂控制进行化学分离的新型应用开辟了道路.
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