Extended Born-Green equation: A new approach for determining pair potentials in disordered systems

The Born-Green equation was tested using molecular dynamics data for liquid rubidium at 319 K. The unsatisfactory results of this equation for the pair potential are caused by the insufficient precision of the Kirkwood approximation for describing the triplet correlation function g₃(r,s,t). A more realistic ansatz for g₃(r,s,t) was employed in the formulation of an extended Born-Green equation. This new approach gives much better results for the potential than the simple Born-Green equation.