In this paper the micro mechanism of BaTiO3 ferroelectric phase transition is studied based on the thermodynamic model using electron cloud model, and further the Curie - Weiss law is explained. The results indicate that the contraction of the electron cloud, as the temperature decreased through Curie temperature, causes oxygen ions shift the equilibrium position, and the Coulomb attraction makes Ti ion shift the equilibrium position causing phase transition; With temperature rising, the ion displacement polarization decreases owing to the electron cloud expansion effect, and the variation of ...
