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The equations of state of forsterite, wadsleyite, ringwoodite, MgSiO3-perovskite, akimotoite, and postperovskite are set up by joint analysis of experimentally measured isobaric heat capacity, bulk moduli, thermal expansion depending on temperature at ambient pressure, and volume at room and higher temperatures. Modified equations of state based on the Helmholtz free energy are used to construct a thermodynamic model. The derived equations of state permit calculation of all thermodynamic functions for the minerals depending on temperature and volume or temperature and pressure. A phase diagram of the system MgSiO3–MgO is constructed based on the Gibbs energy calibrated using the referred experimental points. The seismic boundaries at depths of 410 and 520 km and in the zone D’ are interpreted on the basis of the phase transitions. The global upper/lower mantle discontinuity at a depth of 660 km remains debatable; it is in poor agreement with experimental and computational data on the dissociation of ringwoodite to perovskite and periclase.

Based on the modified formalism of Dorogokupets and Oganov (2007), we calculated the equation of state for diamond, MgO, Ag, Al, Au, Cu, Mo, Nb, Pt, Ta, and W by simultaneous optimization of the data of shock-wave experiments and ultrasonic, X-ray diffraction, dilatometric, and thermochemical measurements in the temperature range from ~ 100 K to the melting points and pressures of up to several Mbar, depending on the material. The obtained room-temperature isotherms were adjusted with a shift of the R1 luminescence line of ruby, which was measured simultaneously with the unit cell parameters of metals in the helium and argon pressure media. The new ruby scale is expressed as P(GPa) = 1870⋅Δλ / λ0(1 + 6⋅Δλ / λ0). It can be used for correction of room-pressure isotherms of metals, diamond, and periclase. New simultaneous measurements of the volumes of Au, Pt, MgO, and B2-NaCl were used for interrelated test of obtained equations of state and calculation of the room-pressure isotherm for B2-NaCl. Therefore, the constructed equations of state for nine metals, diamond, periclase, and B2-NaCl can be considered self-consistent and consistent with the ruby scale and are close to a thermodynamic equilibrium. The calculated PVT relations can be used as self-consistent pressure scales in the study of the PVT properties of minerals using diamond anvil cell in a wide range of temperatures and pressures.