Destruction of magnetization during TOCSY experiments performed under magic angle spinning: Effect of radial B-1 inhomogeneities

TOCSY experiments performed on liquid-like samples under magic angle spinni ng conditions can exhibit some very peculiar behavior In the most extreme c ases, an almost complete loss of magnetization is observed. The intensity o f the effect depends essentially on the ratio of the radiofrequency field s trength to the speed of rotation of the sample. It is shown in this study t hat the periodic modulation of the B-1 field in the course of the sample ro tation is responsible for this effect. (C) 2001 Academic Press.