Single and collective particle dynamics in liquid Rb-80(RbBr)(20)

International audienceThe temperature (T) dependence of the single and the collective particle dynamics of a melt containing 80 at% Rb and 20 at% RbBr was investigated using neutron inelastic scattering. Compared to pure liquid Rb, the dispersions obtained from the maxima of the longitudinal current correlation function clearly reflect the change of the atomic interaction from a metallic to a dominantly ionic regime. The T dependence of the atomic dynamics in Rb80(RbBr)20 is characterized by a broadening of the spectra resulting in a shift to higher energies in the dispersion and in the spectrum of the velocity auto-correlation function, which was determined here for a mixture of a liquid metal with a molten salt for the first time