98 Perturbation Theories for Fluids and Solids
LJ site–site interactions. The results showed a clear superiority of the first of these
approaches over the other two.
Yetiraj et al. (1990) compared the structure obtained from PRISM with the
PY closure with simulation data for fluids composed of chain molecules modeled
as pearl-necklaces of freely jointed HS of diameter σ.Fortheg(r) obtained from
averaging the intermolecular site–site distribution function g
ij
(r) for n-mers with
n =4, 8, and 16, they found that the theory predicts values too high for reduced
distances r
∗
< 1.5 and quite accurate for larger distances. The predictions for the
compressibility factor were also quite poor. Much better results for the structure were
obtained by combining PRISM ...