(123a) Freezing of Highly Supercooled Water Nanodroplets

Water is the only substance on earth that occurs naturally in all three states in the atmosphere. The rates at which phase transitions involving water occur, the degree to which liquid water can be supercooled, and the kind of solid phases that form are all fundamentally interesting questions. We have followed the nucleation, growth, and subsequent freezing of pure water droplets in a supersonic nozzle apparatus using both Small Angle X-ray Scattering (SAXS) and Fourier Transform Infrared Spectroscopy (FTIR). SAXS showed the droplets had radii r in the range 3