Trains of 2pi or 4pi pulses fail to refocus offsets but can suppress the effects of bilinear interactions such as homonuclear scalar couplings.
Rolf Gruetter, Cristina Ramona Cudalbu, Dunja Simicic, Veronika Rackayová, Guillaume Donati
Mayeul Sylvain Chipaux, Hoda Shirzad