Snowflakes become square with a little help from graphene

An atomically thin layer of water freezes at room temperature to form square ice with symmetry completely alien to water molecules, University of Manchester researchers have found. The breakthrough findings allow better understanding of the counterintuitive behaviour of water at the molecular scale and are important for development of more efficient technologies including filtration, desalination and distillation. Water is one of the most familiar and abundant substances on Earth. It exists in many forms, as liquid, vapour and as many as 15 crystal structures of ice, with the commonly found hexagonal ice being singlehandedly responsible for the fascinating variety of snowflakes. Less noticeable but equally ubiquitous is water at interfaces and confined in microscopic pores. In fact, a few monolayers of water cover every surface around us, even in driest deserts, and fill in every single microscopic crack, for example, those present in rocks. Yet, very little is known about the structure and behaviour of such microscopic water, especially when it is hidden from the view, in capillaries deep inside a bulk material.