Perturbation theory based direct correlation function for fluids with hard core potentials

Abstract

Using second-order Barker–Henderson perturbation theory we are able to derive an explicit expression for the direct correlation function of fluids with hard core potentials. Using the obtained direct correlation function, one can explicitly calculate all thermodynamic properties of simple fluids with hard core potentials. Comparisons with computer simulation data show good agreement for both thermodynamic properties and the static structure factor of the hard core double Yukawa potential.

Keywords:

• direct correlation function
• second order Barker–Henderson perturbation theory
• hard core potentials

Acknowledgement

I would like to thank the Islamic Azad University, Amol Branch, for generous financial support of this research project.