Statical critical properties of gadolinium models

Microscopic models of real ferromagnetic gadolinium are proposed, and their critical properties are studied by the Monte Carlo method. The critical ex ponents alpha (heat capacity), gamma (susceptibility), and beta (magnetizat ion) are calculated The alpha, beta, and gamma exponents are determined by the approximation of the data on the basis of traditional power functions a nd in the framework of the finite-size scaling theory. It is revealed that the critical behavior of gadolinium is affected by the dipole-dipole intera ctions. It is shown that the Monte Carlo method is a powerful tool for inve stigations into the critical properties of complex models in which two type s of weak relativistic interactions are jointly taken into account against the background of each of these interactions. (C) 2001 MAIK "Nauka/Interper iodica".