Simplified chemical-physical theory for liquid metal solutions-II. Composition dependence of the gibbs energy

The composition dependence of the Gibbs energy, enthalpy and entropy of mixing are considered with the simplified chemical-physical theory model. Analytical expressions for all thermodynamic functions and derivatives are given in terms of the model parameters. The Darken stability function is shown to exhibit peaks in the compound-forming Group IIB-VA liquid metal systems. The separate enthalpic and entropic contributions to the Darken function are shown to be much larger than the Darken function but of opposite sign so they tend to cancel. Additional examples of the Darken function and its component parts are given for several binary magnesium systems which exhibit very large negative deviations from ideal mixing behaviour.