VERY LARGE MELTING-POINT DEPRESSION OF WATER IN SILICA

We demonstrate that even far below the melting point, thermodynamic data on water in porous systems indicate that part of the water is in the liquid state. This gives a possibility to study some fractal properties of the pore structure, to obtain thermodynamic data of a largely undercooled melt and also to obtain estimates of interfacial energies. The latter data indicate that ice in pores is covered by a quasi-liquid layer at temperatures down to 100 K.