Motional corrections to distances derived from NMR Data: NH₄Cl, NH₄F, and N₂H₆F₂

Corrections for the effects of zero-point energy vibrations on the second moments of the nuclear magnetic resonance (NMR) spectral lines of NH ₄Cl, NH₄F, and N₂H₆F₂ are considered in detail and new N - H distances are derived. It is found for these particular substances that the corrections to the second moments for librational motions are relatively more important than corrections for bending or stretching motions. It is also found that because of the anharmonicity of the stretching motion the error involved in replacing the derived average of the distance by the equilibrium distance is relatively small.