School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
Chemistry. 2018 Sep 20;24(53):13988-14000. doi: 10.1002/chem.201800524. Epub 2018 Jul 3.
Broadband homodecoupling techniques in NMR, also known as "pure shift" methods, aim to enhance spectral resolution by suppressing the effects of homonuclear coupling interactions to turn multiplet signals into singlets. Such techniques typically work by selecting a subset of "active" nuclear spins to observe, and selectively inverting the remaining, "passive", spins to reverse the effects of coupling. Pure Shift Yielded by Chirp Excitation (PSYCHE) is one such method; it is relatively recent, but has already been successfully implemented in a range of different NMR experiments. Paradoxically, PSYCHE is one of the trickiest of pure shift NMR techniques to understand but one of the easiest to use. Here we offer some insights into theoretical and practical aspects of the method, and into the effects and importance of the experimental parameters. Some recent improvements that enhance the spectral purity of PSYCHE spectra will be presented, and some experimental frameworks, including examples in 1D and 2D NMR spectroscopy, for the implementation of PSYCHE will be introduced.
NMR 中的宽带同核去耦技术，也称为“纯位移”方法，旨在通过抑制同核耦合相互作用的影响来提高光谱分辨率，从而将多峰信号转变为单峰。这种技术通常通过选择一组“活跃”核自旋进行观察，并选择性地反转其余的“被动”自旋来反转耦合的影响。啁啾激发产生的纯位移（PSYCHE）就是这样一种方法；它相对较新，但已经成功应用于一系列不同的 NMR 实验中。矛盾的是，PSYCHE 是最难理解但最容易使用的纯位移 NMR 技术之一。在这里，我们将提供一些关于该方法的理论和实际方面的见解，以及实验参数的影响和重要性。我们将介绍一些增强 PSYCHE 谱谱线纯度的最新改进，并介绍一些实验框架，包括一维和二维 NMR 光谱学中的示例，用于实现 PSYCHE。
