Abstract
Multiple spin echo formation for quadrupole nuclei (I≳1/2) in magnetics having inhomogeneous hyperfine and quadrupole interactions was investigated using two and three pulses technique. It was shown that the ‘‘forbidden’’ echo appearance is possible for the time intervals comparable with the characteristic times of the quardupole and hyperfine broadening. The amplitude drop when the time interval between exciting pulses increases is determined not by relaxation time (as usual) but by inhomogeneity having the larger characteristic time (HFI or quadrupole). Multiple spin echo signal for the two pulses technique is due to the transitions with quantum numbers m2≳m1.1 However, when three pulses technique with ‘‘unusual’’ exciting pulses sequence (τ12≳τ23) is used transitions with m1<m2 take part in generation of some additional echo signals. This is confirmed by amplitude and time dependences for the echo signals.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
