Vanadium-51 nuclear magnetic resonance (V NMR spectroscopy) is a method for the characterization of vanadium-containing compounds and materials. V comprises 99.75% of natural vanadium. The nucleus is quadrupolar with I = , which is not favorable for NMR spectroscopy, though its quadrupole moment and thus the linewidths are unusually small, while its magnetogyric ratio is relatively high (+7.0492 rad Ts), so that V has 38% receptivity vs H. Its resonance frequency is close to that of C (gyromagnetic ratio = 6.728284 rad Ts).
The chemical shift dispersion is great, as illustrated by this series: 0 for VOCl (chemical shift standard), −309 for VOCl(O-i-Pr), −506 VOCl(O-i-Pr), and −629 VO(O-i-Pr). For vanadates, the parent orthovanadate and its conjugate acid absorb at −541 ([VO]) and 534 ([HVO]). For decavanadate, three shifts are observed in accord with the number of nonequivalent sites: −422, −502, −519.
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