Phase diagram for amorphous solid water

We show how the observed transformation behavior of two forms of amorphous solid water can be explained in terms of a first-order phase transition, via a consideration of the limits of metastability associated with this kind of transition. We propose a phase diagram describing amorphous solid water consistent with the available experimental data. We support this phase diagram with thermodynamic and structural results of computer simulations using two distinct water interaction potentials, specifically the ST2 potential of Stillinger and Rahman [J. Chem. Phys. 60, 1545 (1974)] and the TIP4P potential of Jorgensen et al. [J. Chem. Phys. 79, 926 (1983)].