了解表面溶解和结构对多态稳定性的影响:一种结合机械化学和理论方法
Ana M Belenguer1, Giulio I Lampronti1,2, Nicola De Mitri1
1Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , U.K.
Journal of the American Chemical Society
|October 30, 2018
概括
在球磨机中,溶剂度会影响共晶多态的稳定性. 不同的溶剂及其度决定了与表面溶解效应相关的多态结果.
科学领域:
- 固态化学
- 晶体学
- 材料科学
背景情况:
- 多态性对共晶性质和性能产生重大影响.
- 控制多态转化对于药物开发至关重要.
- 液体辅助研磨 (LAG) 为共晶合成和改造提供了一种机械化学途径.
研究的目的:
- 研究溶剂度对神素-胺共晶多态体的热力学稳定性的影响.
- 将多态行为与表面溶剂溶解现象相关联.
- 在球磨机LAG下建立多态平衡的实验条件.
主要方法:
- 使用16种不同的溶剂进行球磨机液体辅助研磨 (LAG).
- 现场粉末X射线衍射 (PXRD) 用于监测多态度和晶体大小.
- 表面位相互作用点 (SSIP) 和SSIMPLE方法用于计算溶解能量.
主要成果:
- 实验确定了16个平衡多态度曲线作为溶剂度的函数.
- 证明了平衡曲线的溶剂依赖变化,表明了多态互转化的合作性.
- 在多态表面上确定了特定的暴露功能组 (形式I上的神系面,形式II上的N-甲基组).
- 在平衡状态下观察到晶体尺寸的溶剂特异性差异.
结论:
- 球磨 LAG 可以实现共晶多态平衡,结果对溶剂类型和度敏感.
- 在LAG条件下,表面溶解在确定共晶多态的热力学稳定性方面起着至关重要的作用.
- 这些发现提供了通过机械化学方法和溶剂选择控制共晶多态性的见解.
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