Multiple-Quantum Transitions in Nuclear Magnetic Resonance of Strongly Coupled AA′BB′ Spin Systems

Abstract

The nuclear magnetic resonance multiple-quantum spectra of thiophene and o-dichlorobenzene have been determined and analyzed. Yatsiv's theory, in spite of the fact that in the present cases simplifying assumptions are not fulfilled, correctly predicts frequencies, frequency shifts, and rf field amplitudes for maximum signal. A single less restrictive assumption is proposed which leads to the same conclusions as Yatsiv's. The intensities observed for MQ transitions are weaker than those predicted and the disagreement increases with the number of quanta involved.