The ab initio projector augmented wave method of the density functional theory is applied for studying energy characteristics of oxygen vacancies and migration pathways in Pr_1−xY_xBaCo₂O_6−δ. It is found that the negative formation energy leads to initial appearance of oxygen vacancies in PrO planes thus providing the pathway for oxygen migration at small δ's. The increase of oxygen vacancy population in PrO planes and replacement of Pr by Y both favor a weakening of CoO bonds, which facilitates the increase in the amount of oxygen vacancies in CoO₂ layers. Moreover, the yttrium dopants enlarge the bottleneck for oxygen jumps along ⟨101⟩ directions over oxygen vacancies in PrO and CoO₂ layers. As a result, the respective ‘zigzag’ oxygen migration pathway becomes predominant with increasing oxygen non-stoichiometry and yttrium doping. Thus, the layered perovskite-like cobaltites give an example of a peculiar diffusion process where minority defects provide the transport channel while majority defects maintain favorable geometry of the migration pathway.

在从头被应用于在镨研究氧空位和迁移途径的能量特性的密度泛函理论的投影缀波方法_1-X ý _X BACO ₂ ö _6-δ。发现负形成能导致PrO平面中氧空位的初始出现，从而为小δ's处的氧迁移提供了途径。PrO平面中氧空位人口的增加和Y置换Pr均有助于削弱Co O键，这有助于CoO ₂中氧空位的增加层。此外，钇掺杂增加了PrO和CoO ₂层中氧空位沿⟨101⟩方向跃迁的瓶颈。结果，随着氧气非化学计量和钇掺杂的增加，各自的“之字形”氧气迁移途径变得占主导。因此，层状钙钛矿状钴矿给出了特殊扩散过程的一个例子，少数缺陷提供了传输通道，而多数缺陷则保持了迁移路径的良好几何形状。