High-resolution NMR spectra of nuclear spin systems under homogeneous interactions in solids exhibiting line narrowing induced by the memory effect
High-resolution NMR spectra of nuclear spin systems under homogeneous interactions in solids exhibiting line narrowing induced by the memory effect
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DOI：
10.1006/jmra.1995.0760
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发表时间：
1995-12-01
期刊：
影响因子：
--
通讯作者：
McDowell, CA
中科院分区：
文献类型：
--
作者：
Ding, SW;McDowell, CA
固体中强均相相互作用下的核自旋系统的高分辨率核磁共振谱，只需在数据采集前进行足够长的脉冲激励即可获得。光谱是定量的，但受相位畸变的影响。通过在激发和采集之间插入重聚焦脉冲，可以提高灵敏度。当样品以幻角旋转时，光谱具有最高的分辨率，但非mas光谱的线宽不显示P-2（cos β）依赖性。用记忆功能理论可以很好地解释这种方法，并给出了静态、幻角纺纱和非幻角纺纱样品的实验结果。(C) 1995学术出版社，Inc。
High-resolution nuclear magnetic resonance spectra of nuclear spin systems under strong homogeneous interactions in solids can be obtained simply by single-pulse excitation with a sufficiently long delay before data acquisition. The spectra are quantitative but subject to phase distortions. By inserting a refocusing pulse between excitation and acquisition, the sensitivity can be improved. The spectrum has the highest resolution when the sample is rotated at the magic angle, but the linewidth of the off-MAS spectrum does not show a P-2(cos beta) dependence. This method can be satisfactorily explained by means of memory-function theory, and many experimental results for static, magic-angle spinning, and off-magic angle spinning samples are presented. (C) 1995 Academic Press, Inc.