固态 (63) Cu和 (65) Cu无机和有机金属铜复合物的NMR光谱学 (I)
Joel A Tang1, Bobby D Ellis, Timothy H Warren
1Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario, Canada N9B 3P4.
Journal of the American Chemical Society
|October 11, 2007
概括
固态铜-63/65核磁共振 (NMR) 揭示了电场梯度如何影响铜(I) 复合体. 本研究的特征是四极合常量和化学屏蔽异质在不同的协调环境.
科学领域:
- 固态无机和有机金属化学.
- 核磁共振 (NMR) 光谱学.核磁共振 (NMR) 光谱学.
- 量子化学和计算建模.
背景情况:
- 铜 (I) 复合体表现出不同的协调几何结构.
- 电场梯度 (EFG) 显著影响四极核的NMR光谱.
- 了解分子结构和NMR参数之间的关系至关重要.
研究的目的:
- 在各种铜 (I) 协调环境中研究固态63Cu和65CuNMR.
- 为了将结构变化和对称性与电场梯度 (EFG) 张量相关联.
- 为了确定四极合常量 (CQ) 和化学屏蔽异构物 (CSAs) 对不对称的铜位点.
主要方法:
- 使用哈恩回声和QCPMG脉冲序列的63Cu和65Cu固态NMR实验.
- 对于高信号对噪声粉末模式的频率阶段采集.
- 31P交叉极化魔力角旋转 (CP/MAS) NMR用于Cu-P旋转对.
- 射线晶体学和理论计算 (哈特里-福克,DFT).
主要成果:
- 观察到的CQ值范围为22.0至71.0MHz,用于不对称的Cu位点.
- 由于大型四极相互作用,Spectra显示了广泛的中央过渡模式 (760 kHz至6.7 MHz).
- 在一些复合体中检测到显著的CSA (1000到1500ppm).
- 结合晶体学和理论的NMR数据,允许确定EFG张量方向和CQ标志.
结论:
- 固态核磁共振对于表征各种铜 (I) 协调环境是有效的.
- 核磁共振相互作用张量参数与分子结构和对称性直接相关.
- 该研究通过详细的NMR分析,提供了对铜 (I) 复合物的电子结构的见解.
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