Calculation of Current Correlations in Classical Fluids via Modeled Kinetic Equations

Abstract

In an earlier paper, the generalized Langevin approach of Mori and Zwanzig has been applied to generate an exact kinetic equation describing the time correlation of fluctuations in the microscopic phase density for a classical many-body system. In the present work, this kinetic equation is modeled using a single-relaxation-time form for the damping kernel, and the solution of this equation is then studied for large and small values of k and _. The modeled kinetic equation is used to calculate transverse and lingitudinal current-current correlations in simple classical liquids, and the results are compared with the molecular-dynamics calculations of Rahman for argonlike systems.