Multiquantum triple-pulse spin-echo signals from quadrupole nuclei in magnetically ordered substances

We analyze theoretically the formation of NMR pulse responses from a quadru pole spin system in which the inhomogeneous broadening of a spectral line i s due to both magnetic and electric quadrupole interactions. We derive form ulas for the moments of formation of multiquantum echo signals in the case of three exciting pulses. For the first time we detected in experiments mul tiquantum spin-echo signals from copper nuclei in ferromagnetic copper sulf ochromite in the cases of double-pulse and triple-pulse excitations. We fin d that there is good agreement between the calculated and experimentally ob served moments of echo signal formation. (C) 1999 American Institute of Phy sics. [S1063-7761(99)01506-1].