Journal of Statistical Physics. Vol. 75, Nos. 5/6, 1994. p. 1119-1135.
The two-dimensional renormalization map of the diamond-hierarchical lsing model in an external field is given, and pictures of the distribution of zeros of the partition function in the complex plane of temperature for varying values of coupling constant and external field are shown. Critical exponents of the model are found, and results are different from those of the Ising model on a two- or three-dimensional regular lattice.