Thermodynamic properties of water in the subcooled region. I

An equation is derived for the free energy difference between water and ice in the subcooled (supercooled) region. The calculated vapor pressure difference between ice and water agrees well with experimental measurements. The free energy difference estimated for water in the form of emulsion droplets and bulk water, although small varies significantly with temperature in the subcooled region and is shown to be proportional to the excess free energy arising from the surface effects inherent to the emulsion systems. The accuracy of emulsion data at temperatures below −20 °C therefore could be much lower than previously assumed. In turn this would distort the anomaly functions and give incorrect critical temperature estimates.