Abstract Novel complex oxides PrBaCoNbO6–δ (PBCN) and PrBaCoTaO6–δ (PBCT) are obtained via solid state reactions. X-ray and electron diffraction data for PBCN and PBCT demonstrate cubic space symmetry (S.G. Fm–3m) of the double perovskite crystalline lattice characterized by the rock salt type ordered arrangement of Co/Nb and Co/Ta and random distribution of Pr/Ba atoms. The ab initio electronic structure calculations reveal that the disordered elementary cell is distinguished with the minimum energy. The optical measurements show that PBCN and PBCT compounds are semiconducting materials having maximum light absorption in ultraviolet (UV) region which is consistent with the computer simulations of electronic structure. The thermodynamic modeling results suggest that the structural robustness of PBCN and PBCT phases at heating may be related with large absolute values of oxygen partial enthalpies.

中文翻译：

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新型钙钛矿型氧化物 PrBaCoTa(Nb)O6–δ 的晶体结构和阳离子排序

摘要 通过固态反应获得了新型复合氧化物 PrBaCoNbO6-δ (PBCN) 和 PrBaCoTaO6-δ (PBCT)。PBCN 和 PBCT 的 X 射线和电子衍射数据证明了双钙钛矿晶格的立方空间对称性 (SG Fm–3m)，其特征在于 Co/Nb 和 Co/Ta 的岩盐型有序排列以及 Pr/Ba 的随机分布原子。从头算电子结构计算表明，无序的基本单元以最小的能量被区分。光学测量表明，PBCN 和 PBCT 化合物是半导体材料，在紫外 (UV) 区域具有最大光吸收，这与电子结构的计算机模拟一致。