Simulation of Water and Ammonia at High Pressure and Temperature : a first principle study of the phase diagram

In this work we present the results of extensive Constant Pressure ab-inito Molecular Dynamics simulations of Water and Ammonia at high pressures and temperatures. New superionic, ionic and metallic phases have been discovered and characterized, and consequence on planetary physics discussed. Large scale demanding ab-initio simulations to compute Water and Ammonia phase diagrams, have been possible thanks to the design and the implementation of an architecture free parallel code, ables to exploit the computational power of modern massive parallel computers.