First-principles models and thermodynamic properties of liquid simple metals: A numerical comparison

We compare several electronic structure models (based on density-functional theory, or pseudopotential theory with linear or nonlinear screening) and liquid structure theories (variational approach or integral equation methods) applied to the calculation of thermodynamic functions in liquid simple metals. The numerical consequences of these choices are shown and discussed. Comparison with other work and experiment is made. A prescription for choosing the bridge function used in the modified hypernetted-chain equation is proposed. The central role of the ionic excess entropy in the study of liquid structure and its relation with the ion-ion interaction is emphasized.