在s-d水平控制的氧化物PbCoO3中的A站和B站收费订单
Yuki Sakai1, Junye Yang2, Runze Yu3
1Kanagawa Academy of Science and Technology , KSP, 3-2-1 Sakado, Takatsu-ku, Kawasaki City, Kanagawa 213-0012, Japan.
Journal of the American Chemical Society
|February 28, 2017
概括
合成的矿PbCoO3在和离子中表现出独特的电荷排序,形成Pb2+Pb4+3Co2+2Co3+2O12四重矿结构. 这种复杂的电荷分布通过各种先进的材料表征技术得到证实.
科学领域:
- 材料科学
- 固态化学
- 凝聚物质物理学
背景情况:
- 矿氧化物 (ABO3) 以其多样化的电子和磁性特性而闻名.
- 电荷在矿中的排序可以带来新的功能.
- 了解复杂的价值状态对于材料设计至关重要.
研究的目的:
- 在高压下合成的PbCoO3中研究电荷分布.
- 为了阐明带有电荷排序的四重结构的形成.
- 探索这些独特的价值状态的稳定机制.
主要方法:
- 高压合成 (12 GPa).
- 密度函数理论 (DFT) 的计算.
- 先进的结构和光谱分析:电子衍射 (ED),同步X射线衍射 (SXRD),中子粉衍射 (NPD),硬X射线光辐射光谱 (HAXPES),软X射线吸收光谱 (XAS).
- 物理性质测量:特定热量,磁性和电性质.
主要成果:
- 发现了一个不寻常的电荷分布:Pb2+Pb4+3Co2+2Co3+2O12.
- 在矿结构的A (Pb) 和B (Co) 位点进行电荷排序的证据.
- 证实了四重矿结构.
- 证明调整Pb 6s和过渡金属3d轨道能量可以稳定Pb3.5+Co2.5+O3的平均价值.
结论:
- 在高压下,矿PbCoO3表现出复杂的电荷排序,导致一种新的四重矿结构.
- 观察到的电荷顺序显著影响材料的性质.
- 调整电子轨道能量提供了一种控制和稳定矿复杂的价值状态的途径.
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