Second critical point in two realistic models of water

• DOI: 10.1126/science.abb9796
• Publication Date: 2021-04-01T17:12:16Z
• Authors: Pablo G. Debenedetti; Francesco Sciortino; Gül H. Zerze
• Keywords: Critical point (mathematics); Metastability; Supercooling; Liquid water

The hypothesis that water has a second critical point at deeply supercooled conditions was formulated to provide thermodynamically consistent interpretation of numerous experimental observations. A large body work been devoted verifying or falsifying this hypothesis, but no unambiguous proof yet found. Here, we use histogram reweighting and large-system scattering calculations investigate computationally two molecular models water, TIP4P/2005 TIP4P/Ice, widely regarded be among the most accurate classical force fields for substance. We show both have metastable liquid-liquid is with three-dimensional Ising universality class.