  The chaotic properties of the three-site antiferromagnetic Ising model on
Husimi tree are investigated in magnetic field. Macroscopic quantity of
three-site antiferromagnetic Ising model is generated by one dimensional map.
It is shown that in certain parameter setting strange attractors of this map
exhibit multifractal scaling. By applying thermodynamic formalism we find
nonanalyticity in free energy as well as in entropy. We show that the
temperature of phase transition depends on parameter of model and varies from
negative to positive value.
