Comments on the behavior of the Yvon–Born–Green equation for the square-well fluid near the critical point

Abstract

The Yvon–Born–Green equation under the superposition approximation was solved numerically for a system of molecules interacting via the square‐well potential with σ₂/σ₁=1.85 in the vicinity of the gas–liquid critical point region. The critical point is located, and the critical exponents are determined. A reciprocal temperature perturbation treatment in the context of the Yvon–Born–Green theory is used in conjunction with previously developed stability criteria to locate the gas–liquid and solid–liquid coexistence regions. The methods employed offer encouragement for the use of perturbation approximations in delineating coexistence regions.