Quasithermodynamic theory of He3 and He4 solutions

The conventional theory of nonideal solutions is modified on the basis of Gorter's hypothesis, and various properties of He³ and He⁴ solutions are investigated. The variation of -temperature with He³ concentration is explained adequately right up to the phase separation region. A comparison between the theoretical and experimental results for excess chemical potentials, excess entropy, and excess enthalpy is then carried out. In view of the recognized complex behavior of the solution in the region 1 to 2° K, the observed satisfactory agreement between theory and experiment may be regarded as a strong support for the assumptions made in our work.