Determining the relative orientation between the chemical shift anisotropy and heteronuclear dipolar tensors in static solids by SEDOR NMR.

The measurement of the dipolar interaction between two spins provides the distance between nuclei. A better structural picture emerges when the distance is combined with the orientation of the internuclear vector in the principal axis system of the chemical shift anisotropy tensor. The SEDOR experiment is used on a static sample of alanine to show that the orientation of the vector connecting the nitrogen and carboxylate carbon nuclei can be accurately determined in the CSA PAS of the 13 C carboxylate spin.