Density fluctuation spectra of expanded liquid 85Rb at different temperatures

Density fluctuation spectra in expanded liquid 85Rb measured at 1373 and 1873 K have been successfully explained using the microscopic theory of density fluctuations in a monatomic liquid. The self-diffusion coefficient occurring in the intermediate self-correlation function which is inextricably linked with the collective dynamics of the system, turns out to be frequency dependent and such a consideration also leads to the reproduction of the observed peak in dynamical structure factor near 4–5 ps−1.