14N nuclear quadrupole resonance and relaxation measurements of sodium nitrite

Abstract

Measurements of the quadrupole coupling constant, asymmetry parameter, inverse linewidth parameter T*2, spin–spin relaxation time T2, and spin–lattice relaxation times T1s and T1l are reported for sodium nitrite in the temperature region from 77–467 °K. The relations between the spin–lattice relaxation times and the transition probabilities W+, WΔ, and W− are derived for a spin one system, and the transition probabilities are calculated from the T1 data. The results are compared with other NaNO2 studies and support the work of Avagadro et al. in the temperature region near the ferroelectric phase transition. They also indicate the existence of short-range order above this transition.