密度函数理论在固态中通过键介导的NMR J合的计算
Siân A Joyce1, Jonathan R Yates, Chris J Pickard
1Tyndall National Institute, Lee Maltings, Prospect Row, Cork, Ireland.
Journal of the American Chemical Society
|August 30, 2008
概括
一种新的NMR J合计算方法准确地预测了键中的固态合. 这种方法揭示了晶格效应对J合有影响,而不仅仅是几何,并为NO合提出了新的实验途径.
科学领域:
- 固态核磁共振 (NMR) 光谱学 固态核磁共振 (NMR) 光谱学
- 计算化学的计算化学
- 水结合相互作用
背景情况:
- 核磁共振 (NMR) J合提供了对分子结构和结合的洞察.
- 固态NMR J合对于理解凝结相中的分子排列至关重要.
- 键显著影响分子性质和相互作用.
研究的目的:
- 应用一种新的方法来计算固态系统中的NMR J合.
- 为了研究有机衍生物和DNA结构中的键介导 (2h) J NN 合.
- 与溶液状态NMR相比,探索晶格效应对J合物的影响.
主要方法:
- 利用最近开发的计算方法来计算固态环境中的NMR J合.
- 将该方法应用于6 - 氨基-1-胺衍生物和脱氧氨酸丝带中的分子内和分子间N-H...N键.
- 计算了孤立分子的J合,并与水晶结构进行比较,包括几何优化.
主要成果:
- 在计算和实验固态J NN合之间取得了优异的定量一致.
- 复制了不同衍生品的J合的差异,并将J NN与瓜诺辛带中的键距离相关联.
- 证明了水晶格子的静电效应显著影响J合,超出了固体和溶液状态之间的几何差异.
结论:
- 开发的方法准确地预测了由键介导的固态NMR J合.
- 水晶格子静电学在固态J合中发挥着至关重要的作用,解释了溶液状态与固态NMR差异.
- 预测 (2h) 跨 N-H...O 键的 J NO 合是实验上可行的,并且与 J NN 合的大小可比.
相关概念视频
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As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are slanted or...
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