Gibbs energy of ices III, V and VI: wholistic thermodynamics and elasticity of the water phase diagram to 2300 MPa

TL;DR

This paper presents new Gibbs energy models for ice phases III, V, and VI, enabling accurate thermodynamic and elastic property calculations of water ice under high pressure and low temperature conditions relevant to planetary science.

Contribution

The authors developed comprehensive Gibbs energy representations for multiple ice phases using new high-pressure volume measurements and vibrational energy calculations, expanding the understanding of water's phase diagram.

Findings

Accurate phase boundary and thermodynamic property calculations for ices III, V, and VI.

Open source SeaFreeze framework includes these representations for broad scientific use.

Application to planetary habitability and seismic modeling in water-rich environments.

Abstract

Gibbs energy representations for ice 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 including ice Ih and water (released as the open source SeaFreeze framework) allow accurate determinations of thermodynamics properties (phase boundaries, density, heat capacity, bulk modulus, thermal expansivity, chemical potentials) and seismic wave velocities over the entire range of conditions encountered in hydrospheres in our solar system (220 - 500K to 2300 MPa). These comprehensive representations allow exploration of the rich spectrum of thermodynamic behavior in the H2O system. Although the results are broadly applicable in science and engineering, their use in habitability analysis in water-rich planetary bodies of our solar system and beyond is particularly relevant.