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来自溶液的有机晶体同质核化的Eyring-Polanyi速率理论
Sven L M Schroeder1,2,3
1School of Chemical and Process Engineering, University of Leeds, Leeds LS2 9JT, U.K.
Crystal growth & design
|January 12, 2026
概括
这项研究使用化学动力学来模拟有机晶体核化,揭示了核化速率和溶解度之间的联系. 艾灵-波兰尼分析提供了一种新的方法,用于从溶解度数据中预测核化速率.
科学领域:
- 物理化学 物理化学
- 结晶科学 结晶科学
- 化学反应工程 化学反应工程
背景情况:
- 有机晶体从超和溶液中均质核化在各种化学过程中至关重要.
- 了解核的动力学和热力学对于控制晶体形成至关重要.
- 现有的模型往往难以准确地预测不同条件下的核化速率.
研究的目的:
- 使用化学反应动力学建模初级同质有机晶体核化速率.
- 为了研究核化速率的温度依赖性,并确定激活参数.
- 建立一种基于温度依赖的可溶性数据来预测核化速率的方法.
主要方法:
- 模型核化作为一阶动态过程,源于大溶液密度波动 (LSDFs).
- 使用Eyring-Polanyi框架分析温度依赖的核化速率,以确定激活 (ΔH‡) 和 (ΔS‡).
- 将分析应用于各种溶剂中的l-histidine和酸的实验数据.
主要成果:
- 核化速率表现出与温度的阿雷尼乌斯行为,其特点是系统特定的,超和独立的速率常数.
- 艾灵-波兰尼分析成功确定了同质核形成的激活参数 (ΔH‡ 和 ΔS‡).
- 使用取决于温度的可溶性数据和激活参数,计算的核化速率被准确地复制, ΔH‡大约是溶液度的12倍.
结论:
- 该研究提供了一个强大的框架 (Eyring-Polanyi) 来从溶解度数据中半定量预测同质核化速率.
- 来自LSDFs的核形成似乎与分子层面的反向溶解过程类似.
- 这种方法为预测结晶行为提供了一种新的方法,对制药和材料科学应用有价值.
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