COMPUTATIONAL PROBLEMS IN THE THERMODYNAMICS OF PHASE EQUILIBRIA AND VAPORIZATION KINETICS

摘要

Hypothetically, two elements may form an infinite number of intermediate phases with different structures. The stability of each phase is determined by its Gibbs free energy, which has one or more minima in the free energy vs. concentration curve. However, most of these hypothetical phases are unstable or metastable with respect to other phases. This is illustrated in Figure 1 which represents schematically the integral free energies of formation of a few of the infinite number of possible phases between two elements, A and B, at constant temperature and pressure. It is seen that most of the hypothetical phases have free energy curve minima which lie above the straight lines drawn to connect the lowest minima in the system under consideration.