Three-body distribution functions in hard sphere fluids. Comparison of excluded-volume-anisotropy model predictions and Monte Carlo simulation

Hard sphere three-body distribution functions predicted by the recently developed Excluded-Volume-Anisotropy (EVA) model are compared with Monte Carlo computer simulation measurements. Two types of simulations, both based on the Widom insertion method, are performed as a function of solvent density (0.1 less than or equal to rho sigma(3) less than or equal to 0.8), solute structure (linear, triangular, and bent 3-bead chain), and solute-solvent sphere diameter ratio (0 less than or equal to sigma/sigma(S) less than or equal to 3). Comparisons of these results with those of previous studies illustrate the accuracy of the EVA model in predicting multi-body distribution functions near contact Separations (and inside of contact), where the Kirkwood-Superposition-Approximation is least accurate. (C) 1997 American Institute of Physics. [S0021-9606(97)51141-X].