Performance of frequency-modulated pulses in NQR

This paper presents an analysis of the performance of frequency-modulated pulses and of pulses modulated simultaneously in amplitude and frequency in the pure nuclear quadrupolar resonance (NQR) spectroscopy of spin 3/2 nuclei. Computer simulations are given of the offset compensation efficiency of such pulses as applied to single crystals. Spin evolution equations were solved numerically. Experimental measurements, using FM pulses, of the³⁵Cl NQR of sodium chlorate (NaClO₃) single crystal and of mercuric chloride (HgCl₂) powder are reported. The results suggest that frequency modulated pulses are alternative pulses to composite pulses in NQR.