Herbst Christian, Riedel Kerstin, Leppert Jörg, Ohlenschläger Oliver, Görlach Matthias, Ramachandran Ramadurai
Molecular Biophysics/NMR spectroscopy group, Leibniz Institute for Age Research, Fritz Lipmann Institute, D-07745, Jena, Germany.
J Biomol NMR. 2006 Aug;35(4):241-8. doi: 10.1007/s10858-006-9040-y. Epub 2006 Jul 25.
The efficacy of hetero- and homonuclear dipolar recoupling employing tanh/tan adiabatic inversion pulse based RF pulse schemes has been examined at high magic angle spinning (MAS) frequencies via numerical simulations and experimental measurements. An approach for minimising the recoupling RF power level is presented, taking into consideration the spinning speed, the range of resonance offsets and H(1) inhomogeneities and the available RF field strength. This involves the tailoring of the frequency and amplitude modulation profiles of the inversion pulses. The applicability of tanh/tan pulse based dipolar recoupling schemes to spinning speed regimes where the performance with conventional rectangular pulses may not be satisfactory is demonstrated.
通过数值模拟和实验测量，研究了在高魔角旋转（MAS）频率下，采用基于双曲正切/正切绝热反转脉冲的射频脉冲方案进行异核和同核偶极重耦合的效果。提出了一种最小化重耦合射频功率水平的方法，该方法考虑了旋转速度、共振偏移范围、H(1)不均匀性以及可用的射频场强。这涉及到对反转脉冲的频率和幅度调制曲线进行定制。证明了基于双曲正切/正切脉冲的偶极重耦合方案在传统矩形脉冲性能可能不理想的旋转速度范围内的适用性。
