Relaxations Studies of 2IZSZSpin Order with Signal Enhancement by Coherence Transfer

Abstract

The pulse sequence for generating coherence transfer (or polarization transfer) is invoked to enhance the signal of heteronuclear two spin order (e.g. 2IZSZ) in a spin system with CH moiety. This allows the observation of selective conversion of Zeeman order, in a sample with natural abundant 13C nuclei, into two spin order for measuring cross-correlation of chemical shift anisotropy and dipole-dipole interactions. The molecular reorientational correlation time and the orientation of the C–H axis with respect to the principal axes of carboxyl CSA tensor may be determined simultaneously in the relaxation profile of two spin order.