Statistical Mechanics of Mixtures of Bose-Einstein and Fermi-Dirac Systems

Full quantum corrections are applied to Mayer's recent extension of statistical thermodynamics to the multi-component liquid phase. The resulting formulae are too general in nature to permit quantitative interpretation, but qualitatively, in the case of Bose-Einstein systems, the theory predicts a typical lambda-point condensation in momentum space. A Fermi-Dirac isotopic component dissolved to small concentrations in a Bose-Einstein liquid phase, like He3 in He4, is shown to behave to a first approximation independently of the Bose-Einstein degeneracy of the solvent at all temperatures above the lambda-point. The theory appears unable to handle the situation below the lambda-point.