Table of Contents
International Journal of Spectroscopy
Volume 2014, Article ID 641473, 8 pages
Research Article

Two-Pulse Phase Modulation Based Decoupling Schemes for Removing Heteronuclear Spin Interactions in the NMR Spectroscopy of Isotropic Systems: An Analysis Using Experiments and Numerical Simulations

Department of Chemistry, St. Berchmans College Campus, Mahatma Gandhi University, Kottayam, Kerala 686101, India

Received 29 January 2014; Accepted 7 April 2014; Published 15 May 2014

Academic Editor: Guang Zhu

Copyright © 2014 Cyril Augustine. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Heteronuclear spin interactions in solids and anisotropic liquids can be removed by phase modulated decoupling sequences with frequency sweep, such as -TPPM and its variants. The performance of these sequences in isotropic spin systems with regard to the experimental parameters, phase angle, and decoupler offset is presented here. A comparison is made with other commonly used heteronuclear decoupling schemes in liquids, namely, WALTZ-16, GARP, and MLEV. Also, the trajectories of nuclear magnetization vector of abundant nuclei in a simple spin system during TPPM and -TPPM decoupling sequences are traced out using computer simulations.