Flexible equation of state for a hard sphere and Lennard–Jones fluid near critical temperature

Author uses the condition in terms of contact point radial distribution function G(σ,λ(ηc,α)) containing the self-consistent function λ(ηc,α) and condition of continuity at σ/2= contact point, to determine equation of state, (EoS). Different EoSs in terms of built-in parameter, m, can be obtained with a suitable choice of λ(ηc,α) and the present EoSs have less r.m.s. deviation than Barker–Henderson BH2 for LJ fluids, and results are much closer to molecular dynamics (MD) simulations than expectations and reproduce the existing simulation data and present EoS for LJ potential, with the help of a set of minimum single-scaled parameter, a0(ηc,α) for a given reduced temperature, T∗=(1/β𝜖)=1.4,2,3,4,5,6. It has been found that parameter α=1.059128388 can be used to fix up the critical temperature parameter Tc=1.3120(7) to that of a computer simulation result.