Theoretical melting curves for cubic solids at high pressure

The Lindemann law, the fourth-order anharmonic equation of state and a model for the volume dependence of the Grüneisen coefficient in cubic crystals are used to derive temperature-strain-pressure relations at melting. The relations depend for their application on knowing the values of fourth-order elastic parameters which are not measured experimentally. It is shown that these values can be estimated from melting data at low pressure. A comparative study of the results with previous determinations obtained from shock-wave data is given for copper, silver and gold. Finally, the theoretical fourth-order melting curves of the three selected metals are calculated using both the Lagrangian and Eulerian strain measures.