  A diagrammatic kinetic theory of density fluctuations in simple dense liquids
at long times, described in the preceding paper, is applied to a high density
Lennard-Jones liquid to calculate various equilibrium time correlation
functions. The calculation starts from the general theory and makes two
approximations. 1. The general diagrammatic expression for an irreducible
memory kernel is approximated using a one-loop approximation. 2. The
generalized Enskog projected propagator, which is required for the calculation,
is approximated using a simple kinetic model for the hard sphere memory
function. The coherent intermediate scattering function (CISF), the
longitudinal current correlation function (LCCF), the transverse current
correlation function (TCCF), the incoherent intermediate scattering function
(IISF), and the incoherent longitudinal current correlation function (ILCCF)
are calculated and compared with simulation results for the Lennard-Jones
liquid at high density. The approximate theoretical results are in good
agreement with the simulation data for the IISF for all wave vectors studied
and for the CISF and LCCF for large wave vector. The approximate results are in
poor agreement with the simulation data for the CISF, LCCF, and TCCF for small
wave vectors because these functions are strongly affected by hydrodynamic
fluctuations at small wave vector that are not well described by the simple
kinetic model used. The possible implications of this approach for the study of
liquids is discussed.
