On the ability of classic scaled particle theory to reproduce the cavity contact correlation function of water over a large hydrostatic pressure range

The cavity contact correlation function G(RC) represents the density of liquid molecules in contact with the surface of a spherical cavity of RC radius normalized to the bulk density. Recently, the G(RC) function of water has been determined in the TIP4P water model at 25 °C and over a large range of hydrostatic pressure, by means of Monte Carlo simulations [Floris, J. Mol. Liq. 218 (2016) 166]. It is shown that classic scaled particle theory relationships are able to reproduce in a satisfactory way the hydrostatic pressure dependence of G(RC) by using only two input data: the experimental density of water, and the effective hard sphere diameter of water molecules, 2.8 Å, assumed to be pressure-independent. No further information is needed, even though G(RC) should reflect structural features of water.