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.
Bibliographical noteFunding Information:
G.S. Boutis acknowledges support from Award no. SC1GM086268 from the National Institute of General Medical Sciences as well as KITP (Santa Barbara), where this research was supported in part by the National Science Foundation under Grant no. NSF PHY11-25915 . The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute of general Medical Sciences or the National Institute of Health (NIH) . This research was also supported, in part, by a grant of computer time from the City University of New York High Performance Computing Center under NSF Grants CNS-0855217 and CNS-0958379 . We thank V. Oganesyan for discussions relating to the simulations.
Copyright 2013 Elsevier B.V., All rights reserved.
- Average Hamiltonian theory
- Multiple quantum coherence
- Pulse artifacts
- Spin counting NMR