Random field Ising model with four spin interactions

The random field Ising model with four spin interactions is studied within the finite cluster approximation (F.C.A), on square and simple cubic lattic es. We have investigated the influence of the four spin interactions on the phase diagrams of the system. We have shown that for the simple cubic latt ice, the tricritical behaviour due to the random field does not exist for e very strength of the four spin interactions, and that he tricritical point due to four spin intenactions disappears when the value of the random field is large.