论文标题
双重钙钛矿SR $ _2 $ vnbo $ _6 $中相关的阳离子顺序控制
Cation Order Control of Correlations in Double Perovskite Sr$_2$VNbO$_6$
论文作者
论文摘要
双钙壶扩展了新材料的设计空间，并且它们经常容纳在父钙钛矿化合物中不存在的现象。在这里，我们提供了一项详细的第一原理研究，对相关的双重钙钛矿SR $ _2 $ vnbo $ _6 $，其中电子之间的电荷转移和电子相关强度在很大程度上取决于阳离子顺序。通过使用密度函数理论 +嵌入式动态平均场理论，我们表明，尽管V和Nb来自元素周期表中的同一组，但该化合物的电子结构与其两种母体化合物完全不同。我们解释了电子相关对晶体结构参数的影响如何确定材料的金属绝缘体过渡的哪一侧。我们的结果表明，在具有$ d^1 $父母的双钙岩中，Hund金属行为的出现出现，并强调了电子相关对晶体结构的重要性。
Double perovskites extend the design space for new materials, and they often host phenomena that don't exist in their parent perovskite compounds. Here, we present a detailed first principles study of the correlated double perovskite Sr$_2$VNbO$_6$, where inter-cationic charge transfer and strength of electronic correlations depend strongly on the cation order. By using Density Functional Theory + Embedded Dynamical Mean Field Theory, we show that this compound has a completely different electronic structure than either of its parent compounds despite V and Nb being from the same group in the periodic table. We explain how the electronic correlations' effect on the crystal structural parameters determines on which side of the Hund's metal-Mott insulator transition the material is. Our results demonstrate the emergence of Hund's metallic behavior in a double perovskite that has $d^1$ parents, and underlines the importance of electronic correlation effects on the crystal structure.
