The off-resonance effects on 2D NMR nutation of I = 3 2 quadrupolar nuclei are demonstrated with perturbation theory and numerical calculation in static samples. The off-resonant (Δω) rf field (ω1) enlarges a nutation frequency and consequently increases the measurement range of nuclear quadrupolar interaction parameters. When ωe > ωQmax, and arctg( ω1 Δω) = ±54.7 ° (magic angle), the satellite lines (produced by coherence transfers) in a nutation spectrum are superimposed with the line of central transition, and hence the nutation spectrum is simplified and its sensitivity is enhanced. The nuclear quadrupolar interaction parameters of 23Na nuclei in NaΩ molecular sieve are obtained using 2D NMR nutation.
- Molecular sieve
- Quadrupolar nuclei
- Static sample nutation I = 3 2