通过X射线粉末衍射数据在无机宿主材料中定位有机客体
Stef Smeets1, Lynne B McCusker1, Christian Baerlocher1
1Laboratory of Crystallography, ETH Zurich , Vladimir-Prelog-Weg 5, Zurich CH-8093, Switzerland.
Journal of the American Chemical Society
|May 17, 2016
概括
这项研究系统地通过同步射粉衍射来确定有机结构定向剂 (SDA) 在石道中的实验位置. 这种方法精确地绘制了SDA位置和 heteroatom位置,这对于理解石合成至关重要.
科学领域:
- 材料科学
- 晶体学
- 化学合成
背景情况:
- 确定有机结构指导剂 (SDA) 在热带石框架中的确切位置一直是一个持续的挑战.
- 之前的研究依赖于分子建模,缺乏SDA定位的实验验证.
研究的目的:
- 建立一个系统的实验方法来确定岩道系统中SDA的位置.
- 通过实验数据验证和完善模拟的SDA位置.
- 为了阐明异质原子 (如) 在石框架中的位置.
主要方法:
- 采用了六种酸 (SSZ-53至SSZ-60) 的同步粉衍射数据.
- 使用模拟化 (全球优化) 和瑞特维尔德精炼的组合来确定SDA位置.
- 在瑞特维尔德精细化过程中应用几何约束来优化SDA形状和框架原子位置.
主要成果:
- 在岩道内成功检索了SDA的可靠实验位置.
- 克服了以前阻碍电子密度图解的数据质量和对称性不匹配的挑战.
- 确定了原子在酸盐框架中的位置,并提供了对热带石合成的关键见解.
- 实验SDA位置通常与分子建模模拟一致,但也显示出差异.
结论:
- 使用同步射波和瑞特维尔德精细化开发了一种系统的策略,以实验性地确定石中的SDA位置.
- 这种方法提供了关于SDA定位和异质原子位置的关键信息,这对于理解和控制化物合成至关重要.
- 该方法具有广泛的适用性,可以扩展到各种晶体材料中的其他有机客体的定位,包括金属有机框架.
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