hide
Free keywords:
Heteronuclear recoupling; Magic-angle spinning; Cross-polarization; PISEMA; Liquid crystals
Abstract:
A pulse sequence is described for the recoupling of heteronuclear dipolar interactions under MAS. The method is similar to the PISEMA experiment, but employs a well-defined amplitude modulation of one of the two radio-frequency fields. The technique is used for measurements of 1H-13C dipolar couplings in unoriented solid and liquid-crystalline samples.