Hydrogen Bond Studies: 119. A Deuteron Magnetic Resonance Study of Sodium Perchlorate Monohydrate, NaCIO 4 • D 2 O, at 25 °C and — 55 °C

The quadrupole splittings in the deuterium NMR spectrum from single crystals of deuterated sodium Perchlorate monohydrate, NaClO 4 -D 2 O, have been measured at 25 °C and - 55 °C. At room temperature, the 180° flip frequency of the D 2 O molecules is large compared to the difference between the splittings for the two deuterons. The average quadrupole coupling constant (e 2 q Q/h) and asymmetry parameter η are 134.1(4) kHz and 0.621(5), respectively. At -55 °C, the electric field gradient tensors for each of the two deuterons were observed corresponding to slowly flipping water molecules, and e 2 qQ/h and η for the two deuterons are 231.5(6) and 226.7(6) kHz and 0.196(4) and 0.195(5), respectively. The results indicate that the hydrogen positions in NaClO 4 -H 2 O are dynamically disordered