Galdina A. The critical properties investigation of some statistical models

Critical phenomena and phase transitions in two-dimensional statistical models are investigated. The aim is to investigate the thermodynamic stability of Lieb, Baxter, Ashkin-Teller, Potts, hard squares models and of three-spin one. The method of research is thermodynamic method of investigation of one-component ordinary system critical state. The analytical expressions for the whole set of stability characteristics for each model are obtained. The types of critical behaviour in the models are defined. It is revealed the reasons for violation of the scaling law hypothesis in Lieb and hard square models and the reasons for violation the universality hypothesis in Baxter and Ashkin-Teller models. The critical behaviour of real ferroelectrics and ferromagnets after experimental data is analysed and it is compared with model computations. The field of practical use is the experimental data processing for real crystals and modelling the solutions for three-dimentional objects.