When a thermally isolated vessel of liquid water is depressurized to vacuum, part of water will evaporate, remainder will freeze - total heat being split between latent heat of ice and enthalpy of vaporization. I wanted to calculate the proportions - how much will evaporate, and how much will freeze.
The problem is the values of latent heat and enthalpy of vaporization wander quite a bit with pressure, and they are quite hard to find for anything else than 1 bar. I managed to obtain the value for steam (2501KJ/kg), but I'm still not successful with ice - there is a multitude of tables and documents that list a variety of materials at 1 bar, so if there is one that follows the pressure, I was unable to find it.
So - what would be the latent heat of fusion of water at about 612 Pa?