Equation of state of molecular fluids

In statistical physics, the Monte-Carlo method is used in order to obtain reference equations of state to be able to evaluate the validity of theoretical methods such as perturbation theories or integral equations for molecular fluids. With the classical Metropolis algorithm, we determine the equation of state of two-center Lennard-Jones systems (l * = 0.3292 ; 0.63 ; 0.793) for four isotherms (T* = 5, 20, 100 et 300). The various convergence problems appearing in such calculations are pointed out. We compare these Monte-Carlo results with the isotherms obtained by the median potential treated with a Weeks-Chandler-Andersen type perturbation theory. N.B. This paper is a summary of the original paper destined to this meeting. The reader interested by much more details may ask the author for it.