The combination of the random interaction fields' method and the Bethe-Peierls method for studying two-sublattice magnets

In this paper, the concentration magnetic phase transitions are described using the random interaction fields' method in combination with the Bethe-Peierls method. This approach allows us to take into account the correlation between magnetic moments and obtain a more accurate solution for the calculation of the Curie point in comparison with the use of the Kikuchi method, which is considered as the most accurate method in the molecular field theory. As an example, we study the dependence of the Curie point on the concentration of titanium in titanomagnetite. This material is one of the typical natural ferrimagnetics.