Fusion Equation of Metals

An expression of initial slope of meltingcurve of pure metals was obtained as follows:(dT_m/dP)_o=T_(mo)/c, where c=1.09 (N_(at))~(5/3)z~(-1/3),the unit of c is GPa, N_(at) is the atomic concentra-tion (in 10~(28) m~(-3)), z is the valence, T_(mo)is the melting temperature (in k) of metal underone atmosphere. The calculated results forthirty-one metals agree well with experiments.It has also been proved that by using the freeelectron model of melting, the fusion equationof metals is Simon equation (T_m/T_(mo))q=1+(p/d).Two parameters q and d, which have to fit withexperiments in Simon's empirical equation, nowcan be predicted theoretically, e.g. for Mg,giving q=1.56, d=7.88GPa, the calculated meltingcurve in a fairly wide pressure range (0～60GPa)is shown to be close to the experimental one.