Melting curve equations at high pressure

A number of equations for the melting temperature dependence on pressure, T-m(P), based on the two- and one-phase approaches to melting have been obtained. All melting curves have the form T-m = F(P)D(P), where F(P) is the Simon (rising) melting equation and D(P) is the damping function, which asymptotically slopes down under pressure. This form predicts that each solid phase has a maximum melting temperature at positive or negative pressure. The simplest equation of this form is T-m = T-0(1 + DeltaP/a)(b) exp(-cDeltaP), where DeltaP = P-P-0, P-0 is some reference pressure, and a, b, and c are parameter which are identified in terms of thermodynamic values. All melting curve data obey this equation. This implies that there exist no anomalous melting curves. All melting curves, rising, falling, and flattening, as well as curves with a maximum, are normal insofar as all of them can be described by the unified equation.