“…The variational method has been used again quite recently by Sun and co-workers. Thus, the 2Y fluid has been recently used directly to approximate the pure Lennard-Jones ͑LJ͒ fluids, [26][27][28][29][30] their mixtures, 31 and fullerenes. It means that, ultimately, they all make use, in some way, of the knowledge of the properties of the fluid of hard spheres ͑HS͒ and, as such, are not therefore directly applicable to fluids with soft repulsive interactions as, e.g., the EXP6 model.…”