Larsen F H, Jakobsen H J, Ellis P D, Nielsen N C
Department of Chemistry, University of Aarhus, Aarhus C, DK-8000, Denmark.
J Magn Reson. 1998 Mar;131(1):144-7. doi: 10.1006/jmre.1997.1341.
By combination of fast magic-angle spinning (MAS) and detection of the free-induction decay during a rotor-synchronized quadrupolar Carr-Purcell-Meiboom-Gill (QCPMG) train of refocusing pulses, the sensitivity of quadrupolar-echo MAS NMR spectra for the central transition of half-integer quadrupolar nuclei exhibiting large quadrupolar couplings may be significantly enhanced. Enhancements by an order of magnitude may easily be realized while maintaining information about the anisotropic interactions. In the present study the so-called QCPMG-MAS experiment is demonstrated experimentally and by numerical simulations for the two 87Rb sites in Rb2SO4.
通过快速魔角旋转（MAS）与在转子同步四极 Carr-Purcell-Meiboom-Gill（QCPMG）重聚焦脉冲序列期间检测自由感应衰减相结合，可以显著提高半整数四极核中心跃迁的四极回波 MAS NMR 谱的灵敏度，这些半整数四极核表现出大的四极耦合。在保持有关各向异性相互作用信息的同时，可以很容易地实现一个数量级的增强。在本研究中，通过实验和数值模拟对 Rb2SO4 中的两个 87Rb 位点展示了所谓的 QCPMG-MAS 实验。
