Solid-state NMR methods of dipolar modulation and separated local field spectroscopy are extended to magnetically dilute, heteronuclear I2S moieties in polycrystalline systems, and then used to measure the principal directions of the 15N chemical shielding interactions in an NH 2 group. Characteristic features of the dipolar-modulated chemical shift anisotropy powder spectrum are analyzed, and the dependence of the modulation pattern on the relative orientation of the two tensors is discussed. The effect of homonuclear interactions is considered briefly.
ASJC Scopus subject areas
- 物理與天文學 (全部)