Resonance Effects in Mixed Hydrogen-Deuterium Crystals

Neutron scattering measurements of the impurity induced resonance mode caused by orthodeuterium as a substitutional impurity in solid h.c.p. parahydrogen are found to be in qualitative agreement with simple mass defect theory predictions. The samples studied contained 11-, 10-, and 6 at.% deuterium and the observations were made along the [100] and the [110] directions in the basal plane.

Some discrepancies are found to exist in the detailed quantitative comparison of the phonon shifts and widths and in the intensity of the resonance mode