Deuteron magnetic resonance studies. Part 2.—Cupric acetate hydrate-d16

Abstract

Deuteron magnetic resonance has been detected in single crystals of [Cu(CD₃CO₂)₂D₂O]₂; the CD₃ quadrupole splitting is consistent with CD₃ groups undergoing free or hindered rotation about the C—C bond, the deuteron quadrupole coupling constants and asymmetry parameters being 55.6 kHz and 0.127 at 77 K and 55.5 kHz and 0.128 at 273 K . The finite asymmetry parameter is explained in terms of polarization of the C—D bond by the charge distribution of the molecule. The best value at present in this molecule for the C—D quadrupole coupling constant in the static CD₃ group is near 168 kHz, with an uncertainty of at least ±10 kHz; the bond is probably not axially symmetric with η near 0.05. In CD₃X, the deuteron quadrupole coupling constant shows a marked dependence on the substituent X.