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 T_1s and T_1l 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₊, W_Δ, 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.