Role of the reference system in study of fluid criticality by effective LGW Hamiltonian approach

Microscopic equations for the coefficients of the effective Landau-Ginzburg-Wilson (LGW) fluid Hamiltonian are presented in the case of the reference system that consists of hard spheres with a short-range Yukawa attraction. The mean-field level analysis of the critical parameters of the Sutherland fluid, based on the effective LGW fluid Hamiltonian with two different reference systems, namely, widely used pure hard spheres and hard spheres with the short-range Yukawa attraction, is performed. From the comparison with computer simulation data, the superiority of the reference system that incorporates the short-range attraction is shown.