固态NMR铁米接触和双极转移在有机金属复合物和金属烯酸中
Yong Zhang1, Haihong Sun, Eric Oldfield
1Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA.
Journal of the American Chemical Society
|March 18, 2005
概括
密度函数理论准确地预测了固态魔法角旋转 (MAS) 的NMR和单晶NMR/ENDOR光谱,用于偏磁复合体. 这种计算进步有助于对金属蛋白和有机金属化合物的结构研究.
科学领域:
- 计算化学计算化学
- 固态NMR光谱学 固态NMR光谱学
- 超磁性有机金属化学
背景情况:
- 偏磁性有机金属复合物和金属氨酸在使用NMR光谱学进行结构阐明时存在独特的挑战.
- 准确预测NMR和电子核双共振 (ENDOR) 参数对于理解这些系统至关重要.
研究的目的:
- 调查密度函数理论 (DFT) 在预测固态魔法角度旋转 (MAS) NMR和单晶 NMR/ENDOR光谱中的准确性.
- 评估对NMR化学转移和ENDOR超细值的二磁和超细贡献的计算预测.
主要方法:
- 用密度函数理论 (DFT) 方法进行计算分析.
- 计算的固态MAS NMR化学转移,包括二磁性和超精细的术语.
- 计算的单晶NMR和ENDOR超精度值,包括同位素费米接触和二极合.
主要成果:
- 固态MAS NMR化学转移的预测准确度很高 (R2 = 0.967,6.3%的误差).
- 单晶ENDOR超精度值与实验数据有很好的一致性 (R2 = 0.998,误差为1.2%).
- 单晶NMR转移,包括高精度术语,也得到了准确的预测 (R2 = 0.961).
结论:
- DFT方法提供了可靠的预测固态MAS NMR和单晶NMR/ENDOR光谱的偏磁复合体.
- 这些计算能力将增强NMR和ENDOR技术在研究偏磁金属复合物的应用.
- 这些发现对于研究具有较少定义结构的偏磁性金属蛋白特别有价值.
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