Inhomogeneity-free heteronuclear iMQC

Intermolecular dipolar interactions between proton and carbon spins can be used to indirectly detect carbon spectra with high sensitivity. In this communication, we present a modified sequence that, in addition to the high sensitivity of heteronuclear intermolecular multiple quantum coherence (iMQC) experiments, retains the line narrowing capability characteristic of homonuclear zero-quantum coherences. We demonstrate that this sequence can be used to obtain high resolution C-13 spectra in the presence of magnetic field inhomogeneities, both for thermal and hyperpolarized samples, and discuss applications to water-hyperpolarized carbon imaging. (C) 2011 Elsevier Inc. All rights reserved.