Akgüç, Gürsoy Bozkurt2016-01-082016-01-081994http://hdl.handle.net/11693/17548Cataloged from PDF version of article.Includes bibliographical refences.Closed form solution of ‘Hard spin mean field theory’ is constructed and applied to ‘Three dimensional stacked-triangular-system’. The phase diagram of this system is examined. ‘Free energy’ is calculated to reveal the thermodynamically stable state in the phase diagram. A new second order phase transition line is found near the zero external magnetic field. Strong evidence is found for the tricriticality point behaviour in the multicritical region.xi, 36 leavesEnglishinfo:eu-repo/semantics/openAccessQC793.3.F5 A34 1994Field theory (Physics)Lattice theory.Thesis