从设计上来看,Gd(III) 综合体对高场动态核极化进行了改进
Gabriele Stevanato1, Dominik Józef Kubicki1, Georges Menzildjian1
1Laboratory of Magnetic Resonance, Institut des Sciences et Ingéniere Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne , Switzerland.
Journal of the American Chemical Society
|May 24, 2019
概括
研究人员开发了一种新的加多 (III) 复合物[Gd (tpatcn) ],显著改善了动态核极化 (DNP) 核磁共振光谱. 这种稳定,水溶性剂使DNP增强两倍,推进NMR应用.
科学领域:
- 磁共振光谱学
- 协调化学
- 材料科学
背景情况:
- 加多 (III) 复合物在动态核极化 (DNP) 核磁共振光谱学中表现为有希望的极化剂.
- 优化配体设计对于提高DNP性能至关重要.
研究的目的:
- 为了研究一种新的加多 (III) 复合物[Gd (tpatcn) ],用于高场DNP核磁共振光谱.
- 评估减少零场分裂 (ZFS) 对DNP增强的影响.
主要方法:
- 综合和表征[Gd{tpatcn) ]复合体
- 对其水溶性和线条缩小特性进行评估.
- 在9.4T和100K时测量魔法角旋转DNP增强.
主要成果:
- [Gd(tpatcn]复合体表现为稳定,水溶性和窄线形状.
- 观察到DNP增强的二次性改善.
- 与最先进的[Gd(dota (H2O) ]相比,Gd(tpatcn) 综合体增加了DNP的两倍.
结论:
- 调整连接体设计以尽量减少加多 (III) 复合体中的ZFS导致了显著的DNP改进.
- [Gd(tpatcn) ]代表了DNP NMR光谱中的极化剂的新基准.
- 这种进步为DNP NMR的更广泛应用提供了潜力.
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