Thermodynamics of the γ-α transformation of cerium

The thermodynamic functions for cerium in the vicinity of the isomorphous γ-α phase transformation are calculated from the results of adiabatic experiments. The experimental data are approximated within a modified model of a binary solution. This model is fitted to the experimental results. The behavior of the thermodynamic functions in the ranges of temperatures and pressures covering the γ-α phase transformation is actually characteristic of a critical point of the liquid-vapor type. The critical exponent for the density is found to be β = 0.46. The other exponents are virtually identical to those obtained in the framework of the classical models describing the thermodynamic functions in the vicinity of the critical point.