WATER IN CONFINED GEOMETRIES

The dynamics of water molecules in the vicinity of a hydrophilic inter face is modified as compared to that of bulk water. Recent experiments performed in porous silica show that water dynamics is well described by a stretched-exponential intermediate-scattering function. The beha viour of confined water is similar to that of supercooled water at low er (approximate to 30 K) temperature. This temperature shift can be un derstood within the percolation model of water, assuming that only thr ee hydrogen bonds can be formed between interfacial water molecules in stead of four in bulk water.