Holistic Approach for Studying Planetary Hydrospheres: Gibbs Representation of Ices Thermodynamics, Elasticity, and the Water Phase Diagram to 2,300 MPa

Gibbs energy representations for ices II, III, V, and VI are reported. These were constructed using new measurements of volumes at high pressure over a range of low temperatures combined with calculated vibrational energies grounded in statistical physics. The collection of representations are released within the open source SeaFreeze program, together with the Gibbs representation already known for ice Ih and water. This program allows accurate determination of thermodynamics properties (phase boundaries, density, specific heat, bulk modulus, thermal expansivity, chemical potentials) and seismic wave velocities over the entire range of conditions encountered in hydrospheres in our solar system (130–500 K to 2,300 MPa). These comprehensive representations allow exploration of the rich spectrum of thermodynamic behavior in the H2O system. Although these results are broadly applicable in science and engineering, their use is particularly relevant to habitability analysis, interior modeling, and future geophysical sounding of water‐rich planetary bodies of our solar system and beyond. Key Points New X‐Ray diffraction measurements covering the entire range of ice II, III, V and VI using state of the art high pressure techniques The first Gibbs energy equations of states for ice II, III, V and VI (and first equations of state for ice II, III and V) New open‐source code SeaFreeze allows to explore water and ices thermodynamic at all conditions found in solar system planetary hydrospheres