A nearly classical fluid, supercritical Argon at T=183 K and a density of 1.15 g/cc was modeled using a simulation box of 108 atoms interacting through Lennard-Jones potentials with periodic boundary conditions. The real part of the FBSD result is in reasonably good agreement with the classical result, but there is a non-negligible imaginary part. The latter leads to a notable asymmetry of the frequency-dependent transport coeeficient.

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