在从溶液中结晶的2,4,6-三二二中多态
R M Vrcelj1, H G Gallagher, J N Sherwood
1Contribution from the Department of Pure and Applied Chemistry and Department of Physics and Applied Physics, University of Strathclyde, Glasgow G1 1XL, Scotland, UK.
Journal of the American Chemical Society
|July 18, 2001
概括
溶剂类型影响2,4,6-三二 (TNT) 多态性,不是通过结构指导,而是通过影响溶解度和超和,导致不同的晶体形式. 这与奥斯瓦尔德对齐.
科学领域:
- 结晶科学 结晶科学
- 材料化学 材料化学
- 物理化学 物理化学
背景情况:
- 2,4,6-三二二烯 (TNT) 的多态性对其稳定性和特性至关重要.
- 以前的研究表明,溶剂类型直接决定了TNT的多态形式.
- 了解溶剂效应是控制结晶过程的关键.
研究的目的:
- 为了研究溶剂类型在2,4,6-三二二烯 (TNT) 沉的多态性质中的作用.
- 为了确定溶剂立体特异性指导或溶解性是否决定了多态结果.
- 制定TNT和相关化合物的转移稳定形式的隔离规则.
主要方法:
- 从各种溶剂中降落的2,4,6-三二二烯 (TNT).
- 热量测量技术用于研究相位过渡.
- 在现场结晶研究使用同步辐射进行结构分析.
主要成果:
- 多态变异与溶解度和超和度有关,而不是直接的溶剂结构指导.
- 转移性稳定性或形阶段首先沉,然后转化为稳定的单临床形式.
- 溶剂介导的相位转换受溶解度和动力学的影响.
结论:
- 溶剂对TNT多态性的作用主要是动力和溶解性驱动的,而不是立体特异性的.
- 结果与奥斯瓦尔德的阶段定律一致,解释了转移稳定的形式的初始沉.
- 制定规则可以指导在相关系统中隔离元稳定多态形式.
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