Metastable crystallization products and metastable phase diagram of the glassy and supercooled aqueous ionic solutions of LiCl

Abstract The metastability towards crystallization of glassy and supercooled aqueous ionic solutions of LiCl, has been explored as a function of temperature and concentration by a combination of differential scanning calorimetry and neutron scattering experiments. A metastable phase digram obtained under well specified sample thermal treatment has allowed us to define two narrow concentration ranges (or deep wells) for good glass formation. A good description of the metastable phase diagram is given by the superposition of two binary diagrams, H 2 O/LiCl 3H 2 O and LiCl 5H 2 O/LiCl 2H 2 O. The metastable crystallization end products such as LiCl 2H 2 O have been identified by their diffraction pattern which has been measured for the first time. In particular the metastable form of ice, cubic ice I c , could be produced in a controlled manner and its transformation to ice I h accurately followed.