Population enhancement for NMR of the central transition of quadrupolar nuclei in solids is performed by using adiabatic radiofrequency sweeps of the satellite transitions. Single-resonance experiments are reported for 17O, 23Na, 27Al, and 93Nb nuclei in powders of Al2O3, NaNbO3, and LiNbO3, and in Pyrex glass. Experimental techniques using single-coil probe circuits capable of both wideband frequency sweeps and narrowband detection are presented. The combination of population enhancement with cross polarization from 27Al to 17O in α-Al2O3 (corundum) powder is demonstrated. The sensitivity-enhancement technique is robust, with no critical parameters.
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