A model of phase transition induced antiphase boundaries in perovskite and layered perovskite oxides

摘要

A structural model of the antiphase boundaries (APBs) induced by phase transition in perovskite and layered perovskite oxides is put forward. Besides the distortion of oxygen octahedra, the existence of two types of ion with different sizes on A sites in perovskite blocks and their ordering in local areas might be the reasons for the occurrence of APBs. It could explain why APBs exist in SrBi_(2)Ta_(2)O_(9), Bi_(3.25)La_(0.75)Ti_(3)O_(12), La_(2-x)Ba_(x)CuO_(4), and La_(2/3)Ca_(1/3)MnO_(3), but not in Bi_(4)Ti_(3)O_(12) and Nd_(2)NiO_(4) through their specific structure phase transitions. The formation of APBs might reflect the chemical inhomogeneity in local areas. Empirical results support this model.