MODE: Multiply modulated frame technique, excitation and coherence transfer

The study of modulated pulse (MODE pulse) approach for the application in NMR has been in the literature for over a decade. Although the method's purpose was initially to decouple the spins, its application can be extended to broadband excitation, inversion and coherence transfer between spins (TOCSY). In this paper, the experimental validation of the TOCSY experiment with the help of MODE pulse and how the coupling constant varies over different frames are shown. We demonstrate that the TOCSY with a higher MODE pulse will result in less coherence transfer even with the same RF-power, and a lower MODE pulse will require a larger RF-amplitude to achieve TOCSY over the same bandwidth. We also present a quantitative analysis of the error due to fast oscillating terms that can be neglected, giving the required results.