长距离磁顺序在6H六角含和的矿中
Cierra J Foster1, Jie Xiong1, Matt Boswell2
1Department of Chemistry and Biochemistry, The Ohio State University, 100 W. 18th Avenue, Columbus, Ohio 43210, United States.
氧化氧化氧化由于超交换和直接交换相互作用而表现出反铁磁排序. 它们的晶体结构和磁性质被用X射线和中子衍射研究.
科学领域:
- 固态化学和材料科学 固态化学和材料科学
- 磁力和磁性材料的研究.
- 无机化学和结晶学. 无机化学和结晶学.
背景情况:
- 氧化物是复杂的无机化合物,具有潜在的磁性应用.
- 了解晶体结构和磁性排序之间的相互作用对于设计新材料至关重要.
研究的目的:
- 为了合成和描述Ba3Cr2ReO9和Ba2CrReO6.6的多晶样品.
- 研究这些化合物的晶体结构,磁性排序和交换相互作用.
主要方法:
- 固态合成方法 固态合成方法.
- 实验室X射线粉碎衍射 (XRPD) 用于结晶结构的确定.
- 磁力测量和特定热测量用于磁性属性.
- 可变温度中子粉衍射 (NPD) 用于磁结构的精细化.
主要成果:
- Ba3Cr2ReO9和Ba2CrReO6都结晶成为6H六角结构 (P63/mmc).
- 过渡金属离子表现出偏好的位点占用与一些反位点混合.
- 这两种化合物都显示出远程反铁磁排序.
- 磁性结构由Re-O-Cr超级交换和Cr-Cr/Cr-Re直接交换相互作用来控制.
结论:
- 已经阐明了Ba3Cr2ReO9和Ba2CrReO6的晶体结构和磁性排序.
- 磁性属性与超交换和直接交换相互作用一致.
- 由于Cr3d轨道的重叠不足以在生物体内形成金属-金属键.
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