Previous studies of the effects of anharmonicity, and of atomic disorder, in crystals, are to be extended through a combined theoretical and experimental investigation. The objective is to study the width and structure in phonon lineshapes arising from both sources, in extreme cases. Computer programs to apply the molecular dynamics technique are to be developed, and applied to the calculation of the correlation function S(k,f) in both types of system. Inelastic scattering of neutrons will be used to give experimental S(k,f)'s. The experiments will be perforned as a collaboration with the neutron scattering group in the physics division at Brookhaven National Laboratories. Materials to be studied will include argon, aluminum, iron and its alloys, noble metal alloys, and potassium bromine-rubidium bromine mixtures.
