Applying SAFT-type models for the anomalous properties of water: Successes and challenges

Water is the most important, but at same time anomalous substance on earth. Due to its anomalies it a challenge even for advanced equations of state like PC-SAFT, CPA and SAFT-VR Mie predict water’s properties. It believed by some researchers that properties are result structural fluctuations. The recently developed DAPT model consistent with this idea actually able considerable amount anomalies, density maximum speed sound maximum, which promising, we show in work produces also unrealistic results minima maxima isochoric heat capacity. Also DAPT’s accuracy falls high temperatures/high pressure regions where water behaves simple fluid. This reveals further complexity problem since successful should treat as an fluid when necessary. Moreover, all association models fail reproduce especially tetrahedral fraction. may be more accurate representation inclusion steric hindrance cooperativity effects could provide realistic water. • 4 were evaluated thermodynamic Of considered, only showed We considered rarely such tetrahedrality. All failed describe tetrahedrality (quantitatively qualitatively).