Journal of Chemical Physics, Vol.103, No.12, 5027-5030, 1995
Equation of State for Classical Hard-Particle-Like Fluids
We extend earlier studies of the equation of state of classical hard-particle fluids to potentials where there is an attractive tail in addition to a repulsive hard core. Like the earlier work, the approach is based on the arbitrary point, nearest-neighbor probability density function. In the high temperature (hard-particle) limit, a parametrization of the integrated distribution is introduced. By matching the parameters against the coefficients in a seven-term virial expansion, we obtain an equation of state that is in excellent agreement with the results from Monte Carlo, molecular dynamics calculations in both two and three dimensions. The theory is extended to finite0 temperatures by treating deviations from the hard-particle limit as small corrections that can be evaluated using hard-particle distribution functions. A comparison is made with the results from a five-term finite temperature virial expansion for a three-dimensional hard-particle system with a square well attractive potential.
Keywords:MOLECULAR-DYNAMICS;SYSTEMS