Monte Carlo simulations of continuum percolation of 3D well fluids

Abstract

The author investigates the percolation threshold, rho p, of three-dimensional continuum attractive and repulsive square-well, triangular-well and parabolic-well fluids by Monte Carlo computer simulation. He finds that in the hard-core limit an attractive well decreases rho p below the high-temperature limiting value. In contrast a hard shoulder potential produces the opposite trend. The author quantifies the role of the range and shape of the well potential in determining the value of the percolation threshold. He examines the shapes of all the clusters at the percolation threshold, resolved as a function of the number of particles in a cluster, s. The asphericity parameter, A3, describing the instantaneous shape of the cluster, decays slowly from unity, achieving approximately=0.3 by s approximately=70, statistically indistinguishable from the estimated universal value of 0.312 for percolation clusters.