Seemingly ordinary, water has quite puzzling behavior. Why, for example, does ice float when most liquids crystallize into dense solids that sink?
Using a computer model to explore water as it freezes, a team at Princeton University has found that water's weird behaviors may arise from a sort of split personality: at very cold temperatures and above a certain pressure, water may spontaneously split into two liquid forms.
The team's findings were reported in the journal Nature.
"Our results suggest that at low enough temperatures water can coexist as two different liquid phases of different densities," said Pablo Debenedetti, the Class of 1950 Professor in Engineering and Applied Science and Princeton's dean for research, and a professor of chemical and biological engineering.