Sideband Patterns in Dynamic-Angle-Spinning NMR
Sideband Patterns in Dynamic-Angle-Spinning NMR
复制标题
动态角旋转 NMR 中的边带模式
DOI：
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发表时间：
1993
期刊：
影响因子：
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通讯作者：
A. Pines
中科院分区：
文献类型：
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作者：
P. Grandinetti;Y. K. Lee;J. Baltisberger;B. Sun;A. Pines
摘要 众所周知，动态角旋转 (DAS) NMR 可以使用表征旋转器轴相对于磁场的两个方向的各种互补角 (θ 1 、θ 2 ) 来完成。在二维 DAS 实验的演化周期被划分为不相等部分的情况下，例如通过射频脉冲或旋转器重新定向，就会出现复杂的边带图案。我们描述了边带模式的简单理论，并提供了一系列 DAS 角度上光谱的说明性实验结果。使用角度对 (0°, 63.43°) 的 DAS 实验具有 0.83Ω R 整数倍的边带，对于涉及四极核中心跃迁的 DAS 交叉极化实验特别有用。我们的考虑与其他核磁共振实验相关，其中演化时间由扰动分隔的周期组成和/或由不同的有效哈密顿量表征。
Abstract It is known that dynamic-angle-spinning (DAS) NMR can be accomplished using a variety of complementary angles (θ 1 , θ 2 ) characterizing the two orientations of the spinner axis with respect to the magnetic field. In cases where the evolution period of the two-dimensional DAS experiment is divided into unequal parts, for example, by RF pulses or spinner reorientation, a complex sideband pattern emerges. We describe a simple theory of the sideband pattern and provide illustrative experimental results of spectra over a range of DAS angles. The DAS experiment with the angle pair (0°, 63.43°) has sidebands at integer multiples of 0.83Ω R and should be particularly useful for DAS cross-polarization experiments involving central transitions of quadrupolar nuclei. Our considerations are relevant to other NMR experiments in which an evolution time is composed of periods separated by a perturbation and/or characterized by different effective Hamiltonians.