1H-Detected quadrupolar spin–lattice relaxation measurements under magic-angle spinning solid-state NMR

Abstract

Proton detection and phase-modulated pulse saturation enable the measurement of spin–lattice relaxation times of “invisible” quadrupolar nuclei with extensively large quadrupolar couplings. For nitrogen-14, efficient cross-polarization is obtained with a long-duration preparation pulse. The experiment paves the way to the characterization of a large variety of materials containing halogens, metals and more.