From Water Under Confinement to Understanding Life at Subzero Temperatures.

Water in confined geometries is highly relevant to biology, geology, and other fields where the function and properties of materials are significantly influenced by the presence and behavior of water in these environments. The structure and dynamics of confined water are strongly dependent on the confining geometry and its interaction with the interfaces. This review provides a brief overview of water under nano-sized hard and soft confinement, as well as water in living cells and in the hydration shells around biomolecules. Confined water exhibits distinct characteristics compared to bulk water, particularly in terms of nucleation, crystallization, molecular dynamics, and hydrogen bond network. In nano-sized confinements, water can remain in liquid state at extremely low temperatures (from -45 °C to -120 °C, at atmospheric pressure), offering insights into the fundamental physics of water and potentially enhancing our understanding of life in subzero temperature environments.