Scaling of local density correlations in a fluid close to freezing

We simulated the equilibrium properties of some reference model fluids, with hard-core, Yukawa and Lennard-Jones interactions, and compared their local density profiles in thermodynamic states where the residual multiparticle entropy ~RMPE!, an established and rather sensitive indicator of the incipient ordering of the fluid into a more structured phase, happens to vanish. We found that, once interparticle distances have been referred to the average separation between nearest-neighbor particles, the radial distribution functions ~RDF! coalesce—from the second coordination shell onwards—onto nearly the same spatial profile. This property was ascertained for different model systems in different thermodynamic conditions but for the shared zero-RMPE constraint. The emergence of a scaling relation for the RDF’s in the fluid phase further enlightens the nature of the structural condition that is singled out by the vanishing of the RMPE.