Chemical potential vs. Gibbs free energy relationship by Redlich and Kister and the Redlich-Kister polynomial

Abstract

The relationship of Redlich and Kister between the chemical potential and the molar Gibbs free energy of a multicomponent mixture proves to be in contradiction with both fundamental concepts of chemical thermodynamics and mathematical principles. Hence, it is invalid. This invalidity corresponds with the thermodynamically inadequate representation of the prevalent Redlich-Kister polynomial for the mole fraction dependence of the excess Gibbs free energy of a mixture.