Deuteron Magnetic Resonance of Polycrystalline Deuteroammonia

Deuterium magnetic resonance spectra of polycrystalline ND3 have been observed at 75°, 159°, and 185°K. The measured values of e2qQ/h were 156±7 kc/sec at 75°K, and 72.5±0.9 kc/sec at 159° and 185°K. The decrease at the higher temperatures has been attributed to rotational averaging. Single-crystal growth in the polycrystalline matrix was noted at the higher temperatures; it did not seriously interfere with the measurement of e2qQ/h. Proton second-moment measurements were made on a polycrystalline sample of NH3 at 75°K. The moment obtained was intermediate between the moments expected for the cases of fast and slow C3 reorientation. The rotational-transition temperature has been estimated to be 72°±2°K. A lower limit of 1.75 kcal/mole for the reorientational activation energy was estimated. An anomalous absorption peak was recorded in the center of the ND3 spectrum at 75°K. It may possibly be ascribed to a double-quantum transition.