在单个分子水平上发现可逆和位点依赖的质子转移
Zoran Ristanović1, Abhishek Dutta Chowdhury1, Rasmus Y Brogaard2
1Inorganic Chemistry and Catalysis, Debye Institute for Nanomaterials Science , Utrecht University , Universiteitsweg 99 , 3584 CG Utrecht , The Netherlands.
Journal of the American Chemical Society
|October 4, 2018
概括
单分子光显微镜显示ZSM-5的碳酸稳定性取决于当地的化学环境和烯替代物. 这提供了对热带石宿主化学和反应性的新见解.
科学领域:
- 不同质的催化
- 材料科学
- 物理化学
背景情况:
- 石的活性和选择性由质子和转移反应途径控制.
- 对于优化催化过程至关重要的是了解热中碳酸的行为.
研究的目的:
- 直接观察Zeolite ZSM-5中的单个烯衍生碳酸的实时行为.
- 研究影响化物稳定性和反应性的因素.
- 为了阐明石和芳香物种之间的宿主-客人化学反应.
主要方法:
- 单分子光显微镜用于追踪单个碳酸物种.
- 密度函数理论 (DFT) 计算以评估碳酸稳定性
- 多维旋转角固态核磁共振 (NMR) 光谱用于结构阐明.
主要成果:
- 碳酸的光和光稳定性对石的局部化学环境和溶剂分子敏感.
- 碳酸稳定性可以通过烯部分的替代剂进行调整.
- 碳酸和中性状态之间可逆切换的速度因其位置而异.
- 二次碳酸盐与溶解布伦斯特德酸位之间的相互作用影响光状态寿命和过程可逆性.
结论:
- 碳酸和中性状态的相对稳定性取决于替代剂和石框架内布伦斯特德酸位的特定位置.
- 直接观测提供了关于热质石中的芳香物表面移动性和反应性的新见解.
- 单分子光显微镜,NMR和DFT的组合提供了一种强大的方法来研究化物催化反应.
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