Temperature dependent atomic transport properties of liquid Rb

A simple analytical model for atomic motion is used to obtain velocity autocorrelation function (VACF) for liquid Rb. The modified empty-core potential due to Hasegawa et al., which represents the orthogonalisation effect due to s-core states in such sp-bonded metals, is used for electron–ion interaction. The potential parameter rc is determined at different temperatures from the knowledge of structure factor. We find quantitative explanation for the density and temperature dependence of VACF and self-diffusion coefficients. The coherent behaviour of liquid Rb in terms of the dynamic structure factor employing viscoelastic theory has also been studied. Intrinsic temperature effects have been studied through damping term in the pair potential. The predicted results for VACF, cosine power spectrum, mean square displacement, diffusion and viscosity coefficients have been compared with recent available molecular dynamics (MD) data and a good agreement has been achieved.