On the hard core Yukawa fluid of variable range: Monte Carlo simulations and test of the MSA equation of state

A recently proposed analytical equation of state (EOS) for the hard core Yu kawa fluid is tested against results of Monte Carlo (MC) simulations. The D uh and Mier-y-Teran (DMT) equation of state is based on the mean-spherical approximation (MSA) and gives the free energy of the fluid for arbitrary ra nges of the Yukawa interaction. The pressure EOS is compared with results o f new NVT MC simulations for shorter ranges of the potential and with the s olution of the MSA. In all cases, the DMT EOS reproduces very accurately th e MSA results obtained via the energy route. For the longer Yukawa ranges, the DMT EOS agrees well with the MC results but systematic deviations, due to the MSA itself, are noticeable for shorter ranges.