X-ray diffraction data for lead under pressures up to 80 GPa are used together with previous data covering a wider range to determine the equations of state (EOS) for the three different phases which occur under these pressures at ambient temperature. It is shown that the first-order EOS form H11, typical for ‘‘simple’’ solids, describes perfectly all the data when only the values for ${\mathit{V}}_0$ and ${\mathit{K}}_0$ are individually adapted for each phase.

• Received 20 June 1995

DOI:https://doi.org/10.1103/PhysRevB.52.12636