Figure 1

Density of q-TIP4P/F water as function of temperature along selected isobars. (a) Comparison of \(\rho (T)\) from classical MD (open circles) and PIMD simulations (solid circles). Pressures are (bottom to top) \(P={-100},~0.1,~100,~200,~300,~400,~500\) MPa. (b) Density of q-TIP4P/F water from PIMD simulations (solid circles) and experiments (open symbols; squares, left-triangles, up-triangles, right-triangles, and diamonds are, respectively, from Refs.^{12,16,59,60,61}). Pressures are (bottom to top) \(P={-100},~{-50},~0.1,~100,~200,~300,~400\) MPa. Deviations between experiments and simulations are noticeable only at high pressures, \(P>200\) MPa, and low temperatures, \(T<240\) K. (c) Fit of the q-TIP4P/F water densities shown in (a) using the TSEOS (solid lines). (d) Fit of the q-TIP4P/F water densities shown in (b) using the TSEOS (solid lines). Pressures in (c) and (d) are (bottom to top) \(P = ~{-100},~{-50},~0.1,~50,~100,~150,~200,~250,~300,~350\) MPa. The liquid–liquid binodal line and LLCP predicted from the TSEOS are denoted by the black dashed line and red star.