Institute of Chemistry/Organic and Bioorganic Chemistry, University of Graz, Heinrichstrasse 28, A-8010 Graz, Austria.
J Magn Reson. 2013 Jul;232:1-6. doi: 10.1016/j.jmr.2013.04.005. Epub 2013 Apr 22.
Homonuclear two- and multidimensional NMR spectra are standard experiments for the structure determination of small to medium-sized molecules. In the large majority of homonuclear correlated spectra the diagonal contains the most intense peaks. Cross-peaks near the diagonal could overlap with huge tails of diagonal peaks and can therefore be easily overlooked. Here we present a general method for the suppression of peaks along the diagonal in homonuclear correlated spectra. It is based on a spatially selective excitation followed by the suppression of magnetization which has not changed the frequency during the mixing process. In addition to the auto correlation removal, these experiments are also less affected by magnetic field inhomogeneities due to the slice selective excitation, which on the other side leads to a reduced intensity compared to regular homonuclear correlated spectra.
同核双维和多维 NMR 谱是确定中小分子结构的标准实验。在大多数同核相关谱中，对角线上包含最强的峰。对角线上的交叉峰可能与巨大的对角峰尾重叠，因此很容易被忽略。在这里，我们提出了一种在同核相关谱中抑制对角线上峰的通用方法。它基于空间选择性激发，然后抑制在混合过程中没有改变频率的磁化。除了自动相关去除之外，由于切片选择性激发，这些实验也受磁场不均匀性的影响较小，这反过来又导致与常规同核相关谱相比，强度降低。
