Title: Homonuclear J-Coupling Spectroscopy at Low Magnetic Fields using Spin-Lock Induced Crossing Show Chinese title

Title: 同核J耦合光谱在低磁场下使用自旋锁诱导交叉

Abstract: Nuclear magnetic resonance (NMR) spectroscopy usually requires high magnetic fields to create spectral resolution among different proton species. At low fields, chemical shift dispersion is insufficient to separate the species, and the spectrum exhibits just a single line. In this work, we demonstrate that spectra can nevertheless be acquired at low field using a novel pulse sequence called spin-lock induced crossing (SLIC). This probes energy level crossings induced by a weak spin-locking pulse and produces a unique J-coupling spectrum for most organic molecules. Unlike other forms of low-field J-coupling spectroscopy, our technique does not require the presence of heteronuclei and can be used for most compounds in their native state. We performed SLIC spectroscopy on a number of small molecules at 276 kHz and 20.8 MHZ, and we show that SLIC spectra can be simulated in good agreement with measurements. Show Chinese abstract

Abstract: 核磁共振（NMR）光谱通常需要高磁场来在不同质子种类之间产生光谱分辨率。在低磁场下，化学位移分散不足，无法分离种类，光谱仅显示一条线。在本工作中，我们证明可以使用一种称为自旋锁诱导交叉（SLIC）的新脉冲序列在低场下获取光谱。这探测由弱自旋锁脉冲引起的能级交叉，并为大多数有机分子产生独特的J耦合光谱。与其他形式的低场J耦合光谱学不同，我们的技术不需要存在杂原子，并且可以在其原始状态下用于大多数化合物。我们在276 kHz和20.8 MHz下对一些小分子进行了SLIC光谱分析，并表明SLIC光谱可以与测量结果良好地进行模拟。