Abstract
It is pointed out that the spin-1 Hamiltonian H=-J Jij Si Sj-K Jij Si2 Sj2-C Jij (Si2 Sj+Si SJ2)+Δ Ji Si2 with staggered field C represents the Widom-type lattice mixture of bifunctional molecules ab and AA with finite interactions. The structure of the mean-field phase behavior of the model micellar solution is provided partially by that of the symmetrical section of Griffiths’s three-component model.