The physics of liquid water

Liquid water is a particularly complex molecular liquid. This is due essentially to the intermolecular hydrogen bond formation, the local tetrahedral symmetry and the short hydrogen bond lifetime. At low temperatures, the geometric aspects of the hydrogen bond network are dominant. A percolation approach of the spatial distribution of water molecules according to the number of their hydrogen bonds leads to a qualitative explanation of most of the thermodynamic anomalies observed at low temperature. It is presented a short description of this percolation model and of its predictions of structural and dynamic properties of liquid water. Some selected experimental results are presented and intend to justify some of the hypothesis and main results of the theory