
Perturbation Theories for Simple Fluid Mixtures 207
0.0
2.0
4.0
6.0
8.0
10.0
0.0 0.3 0.6 0.9 1.2 1.5
Δ = –0.2
0.0
2.0
4.0
6.0
8.0
10.0
0.0 0.4 0.8 1.2 1.6 2.0
Z
Δ = –0.5
ρ* ρ*
FIGURE 7.7 Compressibility factor Z of two binary equimolar symmetric mixtures of NAHS
as a function of the reduced density ρ
∗
= ρσ
3
. Points: simulation data from Jung et al. (1994b).
Continuous curves: Equation 7.109 with A = 1/2andg
12
(σ
12
) calculated from Equation 7.116.
As a general rule, we can say that theories that work well for pure fluids also do so
for simple fluid mixtures. Thus, for example, Schöl-Paschinger et al. (2005) obtained
very good accuracy for the predicted phase diagrams ...