Electronic properties and crystal structures of double-perovskites, Ba2BiIIIBiVO6,Ba2PrBiO6, and Ba2PrSbO6: First-principles study
Electronic properties and crystal structures of double-perovskites, Ba2BiIIIBiVO6,Ba2PrBiO6, and Ba2PrSbO6: First-principles study
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双钙钛矿、Ba2BiIIIBiVO6、Ba2PrBiO6 和 Ba2PrSbO6 的电子特性和晶体结构：第一性原理研究
DOI：
10.1088/2053-1591/ab97e5
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发表时间：
2020
影响因子：
2.3
通讯作者：
Hasegawa Masayuki
中科院分区：
文献类型：
--
作者：
Nishidate Kazume;Adiko Achy;Matsukawa Michiaki;Taniguchi Haruka;Sato Arisa;Matsushita Akiyuki;Tanibayashi Satoru;Hasegawa Masayuki
在最近的实验中，在双钙钛矿ba2 prbio6中以Sb取代Bi时，观察到明显的带隙增宽。本文利用第一性原理密度泛函理论和Heyd-Scuseria-Ernzerhof杂化泛函研究了一系列双钙钛矿Ba 2 Bi III Bi V O 6、Ba 2 prbio6和Ba 2 prsbo6的结构和电子性质的取代效应。我们发现，以Pr III取代Bi III时，最上面的两个价带消失了，以Sb V取代Bi V时，最下面的两个导带消失了，导致带隙明显变宽。此外，我们的计算表明，Ba 2 PrPr Bi O 6可能是实验中观察到的Pr IV信号的候选来源。我们发现B位的无序原子构型Ba 2 ' B' V B'III O 6被恢复到原来的结构。另一方面，我们的结果也表明了部分b位紊乱对解释实验观察到的带隙的重要性。
In recent experiments, a significant band gap widening was observed when Sb was substituted for Bi in the double-perovskite Ba 2 PrBiO 6. In this work, we study a series of double-perovskites, Ba 2 Bi III Bi V O 6, Ba 2 PrBiO 6, and Ba 2 PrSbO 6 using the first-principles density functional theory with the Heyd-Scuseria-Ernzerhof hybrid functional to investigate the substitution effect on the structural and electronic properties. We find that the two topmost valence bands are disappeared on the substitution of Pr III for Bi III, and the two bottommost conduction bands are disappeared on the substitution of Sb V for Bi V, causing the significant band gap widening. Further, our calculation suggests that the Ba 2 PrPr Bi O 6 is a possible candidate as a source of the Pr IV signal observed in the experiment. We find that the B-site disordering atomic configuration, Ba 2 B''V B'III O 6, are restored to those of the original structures. On the other hand, our results also suggest the importance of the partial B-site disorder to explain the experimentally observed band gaps.