Water and Ice

Abstract

The water phase diagram is extraordinarily complex. In addition to numerous solid phases of ice, studies have pointed to the existence of distinct amorphous phases. It has even been proposed that there may be a liquid-liquid critical point, where two different liquid phases coexist. In his Perspective, Soper highlights the report by Tulk et al., whose results provide evidence against distinct amorphous phases. These phases were believed to be the low-temperature manifestations of the two liquid forms of water. The work raises doubts about the idea that there is a liquid-liquid phase separation in low-temperature water.