The lattice dynamics of ice Ih (H2O, D2O or HDO) were investigated by using inelastic incoherent neutron scattering techniques in the energy transfer range of 0.002 to 0.5eV (16 to 4025/cm). The spectra from D2O which contained various concentrations of H2O (0.5 to 30wt%) were determined. Three main peaks, at about 0.105, 0.185 and 0.408eV, which were associated with 3 localized modes of the defect center, were observed in the neutron spectra. Two Gaussian components could be resolved in one mode, at 0.103 and 0.107eV; thus indicating the existence of 2 different force constants for the H bonds. A lattice dynamics calculation of the H defect in a D2O Ih ice host lattice, based upon this two H-bond force constant model, showed that the 3 modes were in very similar positions to those which were observed in experimental data. In particular, it predicted a splitting of one peak into modes at 0.103 and 0.107eV.

J.C.Li, D.K.Ross: Journal of Physics - Condensed Matter, 1994, 6[49], 10823-37