Influence of Chemical Exchange among Homonuclear Spins in Heteronuclear Coherence-Transfer Experiments in Liquids
Influence of Chemical Exchange among Homonuclear Spins in Heteronuclear Coherence-Transfer Experiments in Liquids
复制标题
液体中异核相干转移实验中同核自旋之间化学交换的影响
DOI：
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发表时间：
1995
期刊：
影响因子：
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通讯作者：
M. Rance
中科院分区：
文献类型：
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作者：
V. V. Krishnan;M. Rance
摘要 分析了化学交换对以异核单量子相干（HSQC）实验和异核交叉极化技术为代表的两种不同类型溶液态核磁共振方法的相干转移效率的影响。实验和理论上都证明，在存在化学重组过程的情况下，交叉极化实验比 HSQC 等自由进动型序列具有显着优势。特别强调的是 I 1 I 2 S 自旋系统，其中两个 I 自旋正在进行相互交换。
Abstract An analysis is presented of the effects of chemical exchange on the coherence-transfer efficiencies of two different types of solution-state NMR methodologies, represented by the heteronuclear single-quantum coherence (HSQC) experiment and the heteronuclear cross-polarization technique. The cross-polarization experiment is demonstrated both experimentally and theoretically to have significant advantages over the free-precession-type sequences such as HSQC in the presence of chemical reorganization processes. Special emphasis is given to a I 1 I 2 S spin system in which the two I spins are undergoing mutual exchange.