在结晶中加入元素的基本反应
Rajshree Chakrabarti1, Lakshmanji Verma1, Viktor G Hadjiev2
1William A. Brookshire Department of Chemical and Biomolecular Engineering, University of Houston, Houston, TX 77204-4004.
概括
晶体生长涉及溶解物分子与曲反应. 这项研究揭示了两步的合并过程,在最终附着之前,释放溶剂并形成中间键,这对于控制结晶至关重要.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 结晶的动力学 结晶的动力学
背景情况:
- 晶体的生长速度取决于溶解物-曲反应,但对键断裂和重建过程的了解很少.
- 在晶体生长部位阐明分子机制对于控制结晶至关重要.
研究的目的:
- 为了研究溶解物分子与晶体扭曲反应的微观结构和动态.
- 了解涉及溶解物纳入晶体的基本步骤.
主要方法:
- 用了四种具有不同功能的溶剂来探测反应路径.
- 结合时间解析的 in situ 原子力显微镜,X射线,光学方法和分子动力学模拟.
主要成果:
- 溶解物分子 (etioporphyrin I) 从溶液中直接到达晶体阶段.
- 溶液与结的结合发生在两个阶段:部分溶解和附着,其次是结合断裂和重新安置.
- 对曲线的初步键强度决定了合并能量屏障.
结论:
- 确定了结晶生长中的速度限制步骤,即溶解物-曲反应.
- 证明了一个中间状态的存在,其稳定性取决于溶剂.
- 这种理解可以指导开发解决方案,以控制工业和自然界的结晶过程.
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