Zero field NMR and NQR with selective pulses and indirect detection
نویسندگان
چکیده
Zero field NMR and NQR spectra are obtained by the application of dc magnetic field pulses to a demagnetized sample. Pulsed dc fields allow for selective excitation of isotopic species and provide a means for coherent manipulation of the spin system in zero field. Using these selective pulses and level crossing techniques, indirect detection of a quadrupolar nucleus may be accomplished via protons without obtaining the proton background signal in the NQR spectrum. Experimental results from a variety of IH, 2H, and 14N homoand heteronuclear systems are presented as an illustration of these techniques.
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