DETERMINATION OF V-51 QUADRUPOLE AND CHEMICAL-SHIFT TENSOR ORIENTATIONS IN V2O5 BY ANALYSIS OF MAGIC-ANGLE-SPINNING NUCLEAR-MAGNETIC-RESONANCE SPECTRA

Magic-angle spinning (MAS) V-51 nuclear magnetic resonance (NMR) spectra of V2O5 have been recorded at various fields to evidence the relative effects of the quadrupole interaction and electronic shielding at the nucleus. A refinement of the spectra using theoretical simulations has been performed assuming a simultaneous existence of these two anisotropic interactions. The relative orientation of the principal axes for both tensors has been obtained. The results agree with previous single-crystal studies. Reliability of the results is discussed. A fundamental indetermination of the actual relative tensor orientations remains, owing to the powder nature of the sample.