A team of chemists from the University of Utah (USA) has just shown that water does not freeze completely until it reaches -13ºC, and not at 0ºC as we usually think. It is at that extremely low temperature when water not only cools but its molecular structure definitely changes and acquires tetrahedral forms, in which each water molecule joins four others, forming what we know as ice. However, even at these temperatures traces of liquid water can remain in solid water, although it lasts for such a short time that it is almost impossible to detect or measure.
Apart from the interest of the research from the point of view of physics, the authors of the study, who publish their conclusions in the journal Nature , assure that for predictions on climate change it can be really useful to know "at what exact temperature is it cools the water and crystallizes into ice. "
