Perturbation Theories for the Thermodynamic Properties of Fluids and Solids

Overview to Perturbation Theories for More Complex Systems 351

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FIGURE 10.4 Structure factor of liquid cesium near the melting point. Points: experimental

data from Waseda (1980); curve: VPT from Lai et al. (1990).

Both approaches yield nearly equal, and very accurate, results for the excess energy,

but the predicted excess entropy deviates more appreciably from the experiment,

with the worse results achieved with the one-parameter approximation. On the other

hand, the values  ∼ 50 obtained from the two-parameter VPT are much lower than

the earlier-quoted expected ones. A similar approach was applied by Bretonnet et al.

(1992) to obtain ...