Hung Ivan, Gan Zhehong
Center of Interdisciplinary Magnetic Resonance, National High Magnetic Field Laboratory, 1800 East Paul Dirac Drive, Tallahassee, FL 32310, USA.
Center of Interdisciplinary Magnetic Resonance, National High Magnetic Field Laboratory, 1800 East Paul Dirac Drive, Tallahassee, FL 32310, USA.
J Magn Reson. 2015 Jul;256:23-29. doi: 10.1016/j.jmr.2015.04.005. Epub 2015 Apr 24.
Spin-locking and cross-polarization under magic-angle spinning are investigated for uniformly (13)C and (15)N labeled solids. In particular, the interferences from chemical shift anisotropy, and (1)H heteronuclear and (13)C homonuclear dipolar couplings are identified. The physical origin of these interferences provides guidelines for selecting the best (13)C and (15)N polarization transfer rf fields. Optimal settings for both the zero- and double-quantum cross-polarization transfer mechanisms are recommended.
针对均匀（13）C和（15）N标记的固体，研究了魔角旋转下的自旋锁定和交叉极化。特别地，识别了来自化学位移各向异性、（1）H异核和（13）C同核偶极耦合的干扰。这些干扰的物理起源为选择最佳的（13）C和（15）N极化转移射频场提供了指导方针。推荐了零量子和双量子交叉极化转移机制的最佳设置。
