Some magnetic properties of theS=1/2 Ising system with the random exchange integral: The Gaussian approximation

The phase diagrams, magnetization curves, and specific heat are examined for the case of square and simple-cubic ferromagnets with quenched randomness of the exchange integral. The calculations are based on the Gaussian probability function. The results are similar to those obtained previously with the Handrich-Kaneyoshi (HK) method only for small values of the disorder parameter {δ}. For large values of {δ} significant differences appear and the Gaussian distribution cannot be approximated by a function of the HK type.