Spinning-sideband patterns in multiple-quantum magic-angle spinning NMR spectroscopy
Spinning-sideband patterns in multiple-quantum magic-angle spinning NMR spectroscopy
复制标题
多量子魔角旋转核磁共振波谱中的旋转边带图案
DOI：
10.1080/00268979809483252
复制
发表时间：
1998
影响因子：
1.7
通讯作者：
Hans W. Spiess
中科院分区：
文献类型：
--
作者：
U. Friedrich;I. Schnell;Steven P. Brown;A. Lupulescu;D. Demco;Hans W. Spiess
最近的兴趣集中在固态核磁共振实验上，该实验在魔角旋转 (MAS) 存在的情况下激发多量子 (MQ) 相干性。此类实验已应用于偶极耦合自旋 I = 1/2 和半整数四极系统。这两种情况的共同特征是在间接 (MQ) 维度中观察到有趣的旋转边带模式。本文从两个不同的机制来回顾这些模式的起源：第一，MQ再转换期相对于激励期哈密顿活性变化引起的偶极或四极相互作用的转子编码（再转换转子编码，RRE）；其次，t 1 维中 MQ 相干性演化过程中相互作用的转子调制（演化转子调制，ERM）。对于总自旋相干性，仅存在第一种机制，而对于低阶 MQ 相干性，两种机制都对模式有贡献。对于偶极和四极模型系统...
Recent interest has focused on solid-state NMR experiments which excite multiple-quantum (MQ) coherences in the presence of magic-angle spinning (MAS). Such experiments have been applied to both dipolar-coupled spin I = 1/2 and half-integer quadrupolar systems. A feature common to both cases is the observation of interesting spinning sideband patterns in the indirect (MQ) dimension. In this paper, the origin of these patterns is reviewed in terms of two distinct mechanisms: first, rotor encoding of the dipolar or quadrupolar interaction caused by the change in the Hamiltonian active during the MQ reconversion period relative to the excitation period (reconversion rotor encoding, RRE); and, second, rotor modulation of the interaction during the evolution of the MQ coherences in the t 1 dimension (evolution rotor modulation, ERM). Only the first mechanism is present for total spin coherences, while for lower-order MQ coherences both mechanisms contribute to the pattern. For dipolar and quadrupolar model sys...