Nuclear Magnetic Resonance Study of Polycrystalline NH4ClO4

Abstract

The second moments of the proton resonance absorption line in polycrystalline NH₄ClO₄ are found to be 1.27±0.02 gauss² at 70°K and 1.18±0.01 gauss² at 298°K; these results are interpreted in terms of reorientation of the ammonium ion about random or nearly random axes. Spin‐lattice relaxation times for polycrystalline NH₄ClO₄ have been measured between 77° and 298°K by the progressive saturation method. These relaxation times are consistent with a barrier hindering reorientation of 2.0±0.6 kcal.