Temperature dependence of phonon frequencies in argon by inelastic neutron scattering

Abstract

Neutron scattering techniques have been used to measure the temperature dependence of phonon frequencies in a free-standing crystal of 36Ar. Dispersion curves were obtained for phonons of transverse polarization with wavevectors in the (100) direction at 4, 40 and 77 K. Comparison with lattice dynamical models indicates that most of the observed frequency shifts are caused by the change in volume of the crystal.