Optic phonon modes and superconductivity in αphase (Ti, Zr)-(H, D) alloys

Neutron scattering experiments have been performed in order to measure the position of the optic phonon modes in hydrogenated and deuterated alpha phase Ti and Zr. The weak anharmonic effects are discussed with respect to the superconducting properties of these materials, especially the observed inverse isotope effect in Zr-(H, D). It is shown that the superconducting behaviour of both Ti-(H, D) and Zr-(H, D) cannot simply be correlated with the position of the optic phonon modes.