新的一维酸盐Cs3Mn2O4的合成,晶体结构和磁性特性
Jürgen Nuss1, Maria A Señaris-Rodriguez, Prasad L V K Dasari
1Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569 Stuttgart, Germany.
Journal of the American Chemical Society
|June 27, 2012
概括
一个新的三元化合物,Cs(3) Mn(2) O(4),表现出Mn(2+) 和Mn(3+) 离子独特的1D电荷排序. 这种材料在12K以下显示复杂的磁性排序现象,由合的反铁磁链驱动.
科学领域:
- 固态化学 固态化学
- 材料科学 材料科学 材料科学
- 磁力学 磁力学 是一种
背景情况:
- 具有混合价值的三级化合物很少见.
- 了解过渡金属氧化物中的电荷排序对于新的电子性质至关重要.
研究的目的:
- 合成和描述一种新的三元 (II/III) 混合价值化合物.
- 研究Cs(3)Mn(2)O(4) 的晶体结构,电荷排序和磁性特性.
主要方法:
- 亚酸/酸盐合成路径.
- 粉末和单晶X射线衍射.
- 测量磁感应度的测量.
- 密度函数理论 (DFT) 的计算.
主要成果:
- 合成了Cs{3) Mn{2) O{4),并确定了其晶体结构 (P2{1) /c).
- 该结构具有1D MnO (((2) ((1.5-) 链,具有Mn ((2+) 和Mn ((3+) 的完全1:1电荷排序.
- 链内部的反铁磁合导致铁磁链,其3D排序低于~12K,呈现场依赖现象.
结论:
- Cs(3)Mn(2)O(4) 是第一个内在杂的A(x) MnO(2) 显示完整的电荷排序.
- 该化合物表现出复杂的磁性行为,由链间合变化引起.
- DFT计算支持反铁磁的顺序作为基本状态.
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