The Boundary Theory for p-T-x i Multicomponent Phase Diagrams

Abstract

The multicomponent phase equilibrium, in which p-T-x i are independent variables, is one of the key problems studied in geology, high-pressure physics and high-pressure chemistry. The equilibrium, as applied to geology, are usually presented in p-T phase diagrams, with invariant composition parameters or temperature-composition phase diagrams, set at different given pressures. We now discuss the p-T-x i multicomponent phase diagrams in this text; such analyses may be more comprehensive, and if so, then they are useful for the researches in geology and applied high-pressure physics. When compared with “isobaric” phase diagrams, there is one additional parameter to be considered. Even for the p-T-x binary phase diagrams, they must be depicted into three-dimensional space, therefore, the problem becomes much more complicated.