Brooklyn College of The City University of New York, Department of Physics, Brooklyn, NY 11210, United States.
Solid State Nucl Magn Reson. 2013 Jun;53:27-37. doi: 10.1016/j.ssnmr.2013.03.003. Epub 2013 Apr 5.
Spin counting NMR is an experimental technique that allows a determination of the size and time evolution of networks of dipolar coupled nuclear spins. This work reports on an average Hamiltonian treatment of two spin counting sequences and compares the efficiency of the two cycles in the presence of flip errors, RF inhomogeneity, phase transients, phase errors, and offset interactions commonly present in NMR experiments. Simulations on small quantum systems performed using the two cycles reveal the effects of pulse imperfections on the resulting multiple quantum spectra, in qualitative agreement with the average Hamiltonian calculations. Experimental results on adamantane are presented, demonstrating differences in the two sequences in the presence of pulse errors.
自旋计数 NMR 是一种实验技术，可用于确定偶极耦合核自旋网络的大小和时间演化。这项工作报告了两种自旋计数序列的平均哈密顿处理，并比较了在翻转误差、RF 非均匀性、相位瞬变、相位误差和偏移相互作用（通常存在于 NMR 实验中）存在的情况下，两个循环的效率。使用两个循环对小量子系统进行的模拟揭示了脉冲不完美对所得多量子谱的影响，与平均哈密顿计算定性一致。还介绍了金刚烷的实验结果，展示了在存在脉冲误差的情况下两种序列的差异。
