Ironside Matthew S, Stein Robin S, Duer Melinda J
University Chemical Laboratories, Lensfield Road, Cambridge CB2 1EW, UK.
J Magn Reson. 2007 Sep;188(1):49-55. doi: 10.1016/j.jmr.2007.06.003. Epub 2007 Jun 15.
A key problem in solid-state NMR is resolving overlapping isotropic signals. We present here a two-dimensional method which can enable sites with the same isotropic chemical shift to be distinguished according to their chemical shift anisotropy and asymmetry. The method involves correlating sideband spectra at different effective spinning rates using CSA-amplification pulse sequences. The resulting two-dimensional correlation pattern allows very accurate determination of the chemical shift principal values in addition to the recovery of parameters for two overlapping patterns which allows the resolution of overlapping signals.
固态核磁共振中的一个关键问题是解析重叠的各向同性信号。我们在此提出一种二维方法，该方法能够根据具有相同各向同性化学位移的位点的化学位移各向异性和不对称性对其进行区分。该方法涉及使用CSA放大脉冲序列关联不同有效旋转速率下的边带光谱。所得的二维相关图谱除了可以恢复两个重叠图谱的参数以实现重叠信号的分辨外，还能非常准确地确定化学位移主值。
