使用"现成"的基于Gd (III) 的极化剂优化动态核极化
Daniel J Cheney1, Paolo Cerreia Vioglio2, Adam Brookfield3
1Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK. frederic.blanc@liverpool.ac.uk.
Physical chemistry chemical physics : PCCP
|September 11, 2024
概括
加多 (Gd3+) 化合物是用于神奇角旋转 (MAS) 动态核极化 (DNP) 的有效极化剂. 确定了加多酸 (Gd(NO3) 3) 和其他加多来源的最佳度,以提高NMR信号灵敏度.
科学领域:
- 固态核磁共振 (NMR) 光谱学 固态核磁共振 (NMR) 光谱学
- 动态核极化 (DNP) 是指动态核极化.
- 偏磁性放松剂 偏磁性放松剂
背景情况:
- 魔力角旋转 (MAS) 动态核偏振 (DNP) 使用磁性金属离子来增强NMR信号的灵敏度.
- 酸 (Gd (NO3) 3) 之前已经被证明是一种具有成本效益的"现成"DNP极化剂.
- 需要进一步的研究来优化Gd3+度,并探索MAS DNP的替代加多来源.
研究的目的:
- 为了确定MAS DNP.的Gd(NO3) 3的最佳度.
- 评估各种随时可用的加多化合物作为MAS DNP极化剂的有效性.
- 了解影响不同Gd3+源的DNP性能的因素.
主要方法:
- 在DNP实验中Gd(NO3) 3度的系统变化.
- 测试不同的加多盐 (GdCl3,Gd2(SO4)3,GdBr3,Gd(OAc) 3作为极化剂.
- 对NMR信号增强,极化积累时间和电子磁共振 (EPR) 放松时间的分析.
主要成果:
- 发现最佳Gd(NO3) 3度为1H和13C的20mM,15NNNMR的40mM.
- 各种加多化合物 (GdCl3,Gd2(SO4)3,GdBr3) 有效地作为DNP极化剂,产生可变信号增强.
- Gd(OAc) 3的性能降低,可能是由于局部不对称性和酸盐连接体的放松效应.
结论:
- Gd(NO3) 3度显著影响DNP性能,为不同核确定了特定的最佳值.
- 一系列常见的加多盐是MAS DNP应用中Gd(NO3) 3的可行的替代品.
- 加多复合物的化学环境和特性影响其作为DNP极化剂的有效性.
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