Computer simulation of the generalized brownian motion. II. An argon particle in argon fluid

We introduce a new method, based on the theory of stationary stochastic processes, to represent by an analytical reference model a large class of autocorrelation functions known numerically.The analytical reference model is then used to give a very accurate representation of the velocity autocorrelation function of argon near the triple point by a Mori continued fraction truncated at very high order (up to 25 Mori coefficients). Under some restrictive hypothesis, the results of this analysis together with an appropriate numerical algorithm, permit the simulation of generalized brownian dynamics of an argon particle in argon fluid in a realistic way.