Author name: Surendra K. Saxena

The validity and usefulness of thermodynamic models commonly used to model the physical and chemical properties of Earth’s interior at high to ultrahigh pressures and their associated geophysical databases are discussed. All calorimetric data used in these models must have the quality of fitting to experimental phase diagrams derived from work not only at high temperatures and pressures but also under ambient conditions. The density and temperature profiles calculated for Earth’s mantle and core and the phase diagram of iron calculated under core conditions illustrate how thermodynamic modeling helps us understand the physics of Earth’s deep interior.