ABSTRACT

Introduction ............................................................................................................ 5

Stability Limit Conjecture..................................................................................... 6

Liquid-Liquid Phase Transition ......................................................................... 6

Singularity-Free Scenario...................................................................................... 7

Conclusion .............................................................................................................. 7

References ............................................................................................................... 8

Water has long been a source of fascination on account of its peculiar

physical properties. It is the only chemical compound that occurs naturally

in the solid, liquid and vapor phases. If sufficiently cold, it becomes more

compressible and less dense when cooled, and less viscous when

compressed. Its dielectric constant in the normal liquid range is unusually

large, and its melting and boiling temperatures are uncommonly high for a

non-metallic hydride. Liquid water’s anomalies become more pronounced

when it is cooled below the freezing point without crystallizing (super-

cooled) (Debenedetti, 2003). Speedy and Angell, (1976) showed that a variety

of thermodynamic and transport properties of water in the supercooled state

appear to diverge upon power-law extrapolation to 2458C, that is to say a

few degrees below the homogeneous nucleation temperature. Since then, an

important and uninterrupted body of experimental, theoretical and

computational work has sought to understand the physical properties of

cold, non-crystalline, metastable forms of water, and in particular to provide

a unifying theoretical framework within which both the microscopic origin

and the phase behavior implications of the apparent divergencies can be

understood. Although such a definitive interpretation is not yet available,

important progress has been made, and the number of thermodynamically

consistent interpretations that can explain experimental observations is very

small.