Simultaneous selective detection of multiple quantum spectra

A three-dimensional multiple-quantum NMR experiment that produces individual spectra of all quantum orders is described. The separation of different quantum orders is accomplished via Fourier transformation with respect to the phase of the first two pulses of a generic three-pulse multiple-quantum sequence. This dramatically reduces the time required to obtain several selectively detected spectra and enhances the sensitivity and digital resolution from that obtained using the original two-dimensional technique. The experiment is demonstrated on the protons of para-chlorotoluene dissolved in the nematic liquid crystal Merck ZLI-1132.