Comparison of phase diagrams of H2O, D2O, and inert substances

Abstract

The phase diagrams for the light H2O, heavy D2O water, and inert substances (Ne, Ar, Kr, and Xe) have been compared. A method of choosing the starting point for entropy and internal energy was proposed. It allowed testing the principle of corresponding states using caloric variables. In the given coordinates of temperature, pressure, and chemical potential, the water isotopologues form one group of substances and have similar phase diagrams. The inert substances in the same coordinates form another group of substances with similar phase diagrams. The phase diagrams for inert Ne with significant de Boer quantum parameters differ to a certain extent from the phase diagrams of other inert substances.